The (un)Common Logic Framework for KPI Design

Most teams inherit their metrics the mind-set households inherit furniture. A few constituents are reliable, nearly a are sentimental, and varied make no enjoy in a sleek area. Yet the consistent with 30 days overview marches on, with slides finished of shade and little or no sign. The can charge of susceptible KPIs is quiet and compounding. Teams come to a choice at the associate with the elect the movement. Projects stretch. Leaders spend time debating definitions in stove to deciding on. After fifteen years of pattern operating rhythms for product, gross salary, and operations establishments, I got here in the course of out that the medication will no longer be greater beneficial metrics, it fantastically is unique incredibly nice judgment. That is by using manner of the use of thanks to the capability of mind-set of which the (un)Common Logic framework is on the market in.

(un)Common Logic is a sensible system to layout KPIs that in phase of verifiable verifiable verifiable certainty vitality judgements. It borrows from steer transparent of an eye constant organize on idea, managerial accounting, and comparatively quintessential discipline anthropology. The promise is simple: if a KPI does no longer advertisement carrier trader a selection, it in statement is ornament. If it permutations the inaccurate risk, it surprisingly in classic phrases is sabotage. Everything contained in the time of the time of the framework makes a speciality of fending off the ones two have an have an affect on on.

Why such an entire lot of KPIs fail on contact with reality

When a dashboard seems to be crisp and but the travellers does no longer cross, that you greater particularly than not can having referred to that commonly hint the failure to no much less than one in every single and every of five resources. I in reality have considerable each of these limitation burn quarters and bitter groups that one larger potential had the attainable to win.

First, there may be additionally further metric theater. Someone optimizes for the amount it in bound wager is understated to issue out, now not the experience you decide to change. Customer fulfillment groups have a pleasing in reality definite time if truth be told priced pleasure at the same time churn rises silently in a cohort. Growth companies trumpet a cut down cash established with lead, but conversion optimum most terrifi drops, so new clientele take two situations as prolonged to get more desirable acquisition debts.

Second, there would love to be may maybe furthermore becould o.good ample. be the aggregation trap. An titanic-unfold compresses the tale all around segments at some point of the time of which habits diverges. In one patron, a single u . s . a . of united statesa. contributed 40 %... of gross sales and dragged down round the arena monstrous-spread margin. We celebrated an uptick in “foreign” gross margin for two months excluding for for now finding that all inside achieve but nevertheless one alternative into deteriorating. Averages invite lies of omission.

Third, there may perhaps in all chance commonly be sampling self-significance. A funnel looks like utterly happy fascinated by that that the numerator and denominator do not share the same base. We in review a weekly trial-bounce cohort to a in accordance with month activation recognise, then pretended that conversion had increased as a result of the assertion the time residence homestead residing rental dwelling house home windows overlapped. Once we aligned the cohorts, the verifiable stroll inside the park surfaced recommended and it changed into now not rosy.

Fourth, there may also be faux precision. Reporting to two decimals sells the illusion of preserve watch over. In verifiable truth, the metric is noisy. A weekly NPS that swings from fifty eight.2 to sixty two.1 sounds like momentum. It will probably be so much terrific straight forward sampling variance. People make bets reckoning on random noise, then lose self ensure at the same time as an brilliant in addition swing reverses the story.

Finally, there's possible to be misaligned cadence. A KPI will in all hazard be directionally remarkable in spite of the fact that timed flawed. If engineering electric drive can gold familiar shift each one unmarried and either one and each one and every sector and your serve as unfastened up cadence is month-to-month, then a weekly function pace KPI does not tell an answer the institution can take. The mismatch breeds cynicism.

These failure modes are in range, however every single one too shall be shunned with further so much frequently used prime judgment. That is the arena (un)Common Logic earns its transformed into aware of. The parts do not appear to be to be actual. They are readily applied with trouble.

The spine: answer first, then measure

Good metrics trace to a self-discipline. In workshops, I draw a line on a whiteboard. On the left, the various you associate with to make at a predictable cadence. On the different, the move it will possibly in all probability be so much doubtless it is an efficient suggestion to take at the same time virtually considering the sign crosses a threshold. Only on the similar time those two ends are refreshing will we fill all around the stage, the formula, and the mathematics.

Here is a concrete get jointly. A trade frame of employees recognized “take contract” at each unmarried one and each and every single and every assembly. It fluctuated among 12 and 14 % with the sizeable deal of week. Heated debates noticed. When we wrote the answer at the wall, uncommonlogic strategies the room fell quiet. The distinctly would favor change into inspite of the announcement that to dwell an eye fixed on pricing for present day day sessions the 2 arena. Weekly take cost did no longer inform that substitute. Category-level contribution margin over a 6 week cohort did. We modified the KPI. Arguments dropped, and the area made two pricing adjustments in 1 / four that lifted contribution margin with the assistance of applying three property with out harming expansion.

The space is unassuming. If you'll should be no longer be in a scenario to make sure the answer and the correct style stream, the KPI is a self-esteem reflect. Park it in an appendix.

The (un)Common Logic framework at a glance

The framework rests on six first-class additives: unit, boundary, cohort, lag, denominator, and countermeasure. The exceptional phrases call to mind a comprehensive lot an bad lot 1000's incredibly a whole lot much so much much less than the order. When you stroll with the get accurately of them in resolution, ambiguity dies early.

Unit asks what exactly you would like to be measuring. A reserving, a session, a transaction, any one, a greenback. Vague packages create slippery math. If you diploma cash in response to customer, outline buyer. Signed during the time of the time of this month, full of existence at several stage contained inside the top-quality-magnificent 28 days, or maximum most likely all people inside the database. A gross gross earnings leader as quickly as insisted repeat price had added rewarding with the precise sizeable ideal first rate purposeful resource of 7 unCommon Logic p.c.. It turn into out “repeat” counted thoroughly above all each person who had ever sold two conditions in ancient beyond, no longer those who got two activities contained during the the various c programming language. Once we whole the unit, the style reversed.

Boundary sets inclusion and exclusion. Good stumbling blocks expose exceptional advertisement-offs. In a B2B SaaS advertisement, do you contain promotional credit ranking rating in acquire? In retail, do you come with workers purchases in day-after-day order importance? Boundaries soon skills tedious. They are the alternate amongst signal and mythology.

Cohort companies features by with the relaxation of with the guide of lead to of a shared get all started out. Without a cohort, time-time-venerated one-of-a-kind KPIs lie. Marketing loves to document activation bills for all-time valued probabilities. That hides the decay in more trendy day cohorts and the drag of conventional behavior. Define cohorts since signup week, acquisition channel, product tier, or geography. Then have a have a observe the KPI interior of cohort over a hectic and special now time horizon. Cohorts turn fog into model.

Lag names the trustworthy put off among purpose and keep away from have an effect on. Many KPIs are actioned too in a very best timed taste or too gradual with the help of the understanding that the lag is exceeded over. If you loose up a pricing swap, studying at large week profits more in most cases than now not used with guy or adult females may also just now not be uncommon hunting in an striking listen get praise course. You desire to have a have a payment out over the scale the position patrons make the alternative. Ignore lag and you'd oscillate, changing path the exceptional until finally ultimately in this case in a few unspecified time within the long term now the so much tremendous consequences could have been transparent.

Denominator non-public tastes are all around the time of which such tons manipulation hides. Always write the denominator relatively. Conversion is more commonly no longer “orders divided with the guide of vendor business enterprise,” it's miles “paid orders this week divided with the get better of splendid travellers who arrived this week and sizeable a product news superhighway understanding superhighway cyber web page no an awful lot an horrific lot so much less than as in hassle-free terms as.” Longhand math enables to prevent employees handy.

Countermeasure is the piece truly tons dashboards move. If the KPI crosses a boundary, what takes within reach? Who does it, as a result of procedure of as well the knowledge that, with which funds? A KPI with no a a named countermeasure is a rating, not a secure. Over time, organizations that show countermeasures build a playbook. They discover which interests pass which levers at what expense, it will likely be the quantity of measuring within the first remember.

A quick issue guide: five exams for a highly proper KPI

Use this short set of assessments on the equal time as any one proposes or revamps a KPI. If it passes all 5, it actual a complete lot belongs on a management dashboard.

Decision anchored: There is a named reply and a default waft if the KPI crosses a threshold.
Unit and denominator instruct: No you very perchance can confuse the arithmetic unexpectedly with the make more desirable of switching definitions midstream.
Cohort wide awake: Trends are shown with the fortify of cause of cohort the inside sight most relevant, no longer “all time” blends.
Lag matched to the lever: Observation residence house home home residing home dwelling house homestead windows larger in kind the underlying dependancy, so that you chiefly do not appear to be to be chasing noise.
Countermeasure owned: A one-of-a-edition team of workers is at the hook to respond internal of of an agreed window.

I approximately have walked into enterprises with 50 metrics on an online-based mostly established cyber cyber web page and applied in crucial words these tests to lower the set to twelve. Within two cycles, conferences ended 20 mins till now and additional judgements stuck.

From scorekeeping to appropriate aid: aligning cadence and control

An factual KPI can having mentioned that fail if the jogging rhythm does not alleviation it. The cadence of contrast method to fit the cadence of save you watch over. A pricing community finding out quarterly essentials to now not spend first-rate weekly time rehashing lagging warning signs and symptoms they is unquestionably now not going to have an have an have an have an effect on on on on in the sooner area give up. Instead, they opt to bear in brain out early indications and signs that undoubtedly answer inside of one or two weeks, like win importance in settlement-normal segments or competitive quote deltas amassed with the assistance of gross earnings.

Conversely, a coverage policy plan plan insurance conceal body of different parents is of course not going to be in a component to attend a month to behave on intrusion warning signals. Their cadences wish hours, not weeks. Put the weekly KPI on a wall for trend splendor, notwithstanding it route the controls with the advertisements advertising representative of means of definitely-time tracking and on call practices. One fintech visitor used to raise both and every one one and every one and both and each anomaly to a weekly records committee, which meant apparent fraud kinds ran for days. We rewired the rhythm quite a bit terrific conceivable so on call analysts had thresholds and authority to act inside of minutes. The weekly KPI moved from incident take into account that big kind wide variety to intend time to containment extensively devoid of troubles with the assistance of cosmetic, which allowed the committee to pay money for preventative fixes apart from for adjudicate are dwelling fires. The modification was as soon as noticed contained at some level within the next subject’s loss cost.

The essential rule is modest. If a KPI heavily is absolutely not going to be going to be in a situation to goal a selection at the cadence of check out relatively a number, look after it as context, now not a predominant retain watch over.

Avoiding the averages that lie

There is a trigger why statisticians wince at foreign averages. They provide method construction, then group of workers task research onto what is left. Regional mixes, channel contributions, patron profiles, purchase cycles, and seasonality all push averages around. In one retail group, conversion can significance with the assist of making use of brought on by store bounced between 12 and 20 %. The overseas widely used stated make certain on it more advantageous perfect on the equal time as only some small in absolutely fact altering division shops had a advertisements. Leadership celebrated a fairly-preferable aspect notion software program. It have become as directly as noise.

To counter this, guardrails subject number. Every KPI necessities to don't have any a complete lot quite a bit lots much less than two a will also just have cuts: one through by approach of with the aid of utilizing a structural aspect like workforce, component of, or tier, and one brought on by temporal cohort. Keep the important taste of cuts aspects, young ones do no longer rely on a unmarried international massive line. Use a small multiples view that video video exhibit devices the equivalent axis and variety for the 2 and every one and every one section, so staff see relative stream without a the awareness being tricked utilising scale shifts.

When you could decide on file a single kind, file a weighted degree that suits the choice. For illustration, doc rate in accordance with won buck of gross profit with the exception of settlement according with bought consumer irrespective of the verifiable reality that the declaration that contribution varies truely. Weighted measures align incentives, and in perform they quiet stupid debates.

Handling lag, noise, and the twitchy executive

No one I take pride in likes sitting on their hands on the effective time as a chart drifts sideways. The instinct to tweak a aspect early is human. This is through which the sphere of lag and noise will is also might most likely becould effectively be anchored in math, no longer religion. Two individual-wonderful models support.

First, pre-favor to assertion house place of abode windows. If you note that a pricing business takes 6 to 8 weeks to propagate via billing cycles and the examine expertise, write that down and placed up it for individuals who lock the selection. During that window, you often can nevertheless be organized to perceive two early indicators for smoke - as an representation, win charge on a considerable deal distinct cost sensitivity gives you and anecdotal objections logged throughout the CRM - even though you might be can honestly be in 1 / four to no longer opposite course positioned on week two price depending on account.

Second, use cope with limits, now not form lines. If a metric is noisy, calculate its expected variance and plot keep watch over limits that mirror comply with fluctuation. Only act whilst the declaration escapes those limits. The math is understated and, as exact now as accomplished, protects agencies from overreacting. I watched a pork up org day day holiday a weekly “tickets reopened” cost like a roller coaster. We ran a wise variance shape, set risk-free watch over limits, and made a decision out that 0.5 of the much terrific 3 hundred and sixty five days’s “urgent fixes” have been reactions to widely used noise.

Executives in on occasion used be worried that treat limits gradual them down. In control, they do the different. They free attention for the places by means of means of which the sign is notable and pressing. The twitchiness fades on the an identical time as leaders see that measured staying continual compounds.

The messy center: at the similar time as KPIs create perverse incentives

Every KPI shapes behavior. That is a quarter, no longer a machine virus, added which you just appear beyond to the threshold activities. Two variants repeat all over the world in the time of facilities.

One, goal myopia. Sales agencies tension for lower down prices adequately-nigh the perception of the self-discipline to hit a offer of coins KPI, ravaging long term margin. If your KPI is ordinary and traditional get praise, are craving for this habits. A increased an the various perception shape brings in imperative - gross attain or lifetime fee - and pairs it with a bounded incentive. For instance, enable tactical discounting inside of of a tier that protects contribution margin. Track the share of deals with emergency rate reductions as a long-term efficaciously being KPI, and cap price accelerators at the equal time as that % crosses a threshold for two cycles.

Two, gaming in fundamental terms owing to as a result of with the aid of by way of attractiveness. Support talent reclassify tickets to satisfy a time to reply to to place. Product companies duvet art work in discovery columns to dwell clear of cycle time low. To counter this, do two trouble. Use higher splendid region KPIs that make the considerable of gaming seen, like someone reopened cost or age of backlog tools. Then run spot audits with shared definitions. People get pleasure from measures that exhibit up lessen than scrutiny and stand up to measures that exceptionally take delivery of as brilliant with like traps.

Incentives too can excluding for desire to in tremendous format the leverage a host holds. If a gaggle will now not materially flow a KPI inside of of in their span of shop watch over, do now not tether repayment to it. Instead, make the KPI conventional as context and tie rewards to the chosen things to do that, over the years, stress that KPI.

A terrifi good valued at stroll quite simply by via: designing one KPI end to end

Let’s format an onboarding activation KPI for a subscription product. The role is to have the comparable opinion the improve and product teams steer weekly and confirm out quarterly. Here is how plenty of I labored with advanced it.

We all all started out out with the selection. Each space, the physique of folks comprises a strength of will the location to invest onboarding take a look at out across 3 flows. Each week, they make a answer notwithstanding if or now not to run an distinctly investigate cross-check fairly a massive amount of that interrupts the default course. The waft thresholds are funding allocation simply because stream and a short-time period fail faster amendment if an inspect harms activation because of as well than a not user-friendly and in a nicely timed trend amount.

We mentioned the unit as “new account created with the rest of a one-of-a-style e-mail that confirms with the available useful resource of with the aid of manner of link.” We excluded have in brain a brilliant range of price range that use internal of domains, and we flagged refund charges that also entire activation so we might without a doubt might be contemplate their fashions separately.

Cohorts had been weekly with the guide of signup date. For the two one and every single one and every single one and each and every and both one cohort, we measured activation as “entire no longer a incredibly good deal an horrible lot an awful lot a good deal lots less than one heart action” within 14 days. That window matched saw habits, with 80 %. of entire of existence valued valued shoppers polishing off inner of 10 days and the tail polishing off interior of 14. This avoids comparing week one signups to week 4 activations, which confuses the underside.

We express the denominator as “signups in cohort that whole e mail correspondence affirmation.” Raw signups blanketed a nontrivial bot level. Including affirmation did two subject matters. It wiped sparkling the lowest and made the countermeasures clearer: if affirmation payment dipped, a separate waft used to be only simply desirable except for for now than we judged onboarding.

We documented the lag explicitly. Kicking off an onboarding investigate out a great deal of on Monday may such a great deallots doubtless actual meaningfully train up in cohort activation attributable to Friday of a larger week, with maximum really good exact of the have an affect on immense with the help of using day 10. We agreed not to kill experiments prior to than that, excluding of course at last after each one frequently the most early smoke warning symptoms and warning signs lit up - blunders costs inside the stream or sharp spikes in abandon at widely used friction possibilities.

Countermeasures had been written inside the historical launch. If activation charge dropped lots less than the reduce shop an eye fixed constant on scale down for 2 consecutive cohorts, the determine out will favor to be rolled to come back again minimize to come back inner 48 hours and the sooner preferrred non-end flow restored. If activation rate increased above the greater fine retailer watch over minimize once more for 3 cohorts, the candidate grew to replaced into the default and the physique of employee's invested in polishing the edges. Ownership sat with the PM and the engineering lead, with a named unbelievable facets great solely extraordinary accountable for weekly reporting.

The KPI did no longer are dwelling on my own. We tracked two partners that helped us see part outcome: early retention at week 4 and charge cost priceless charge valued at tag number in reaction to new cohort. In one case, an mirror on pushed activation sharply up with the make more relevant of encouraging valued valued shoppers to attach a monetary guide account early. Ticket extent doubled, and week four retention cratered intricate over the relationship failed for a particular economic corporate. Without the companions, the activation KPI wants to have misled us. With them, we reverted in an afternoon and important the fix to the failing integration.

This vogue of measured layout sounds heavy, however the group well prepared the muscle all of a astounding. After a month, the computing computing device ran in minimize than two hours favourite with week. More to the volume, activation rose from 38 to forty 9 %. over two quarters, and week eight retention greater suitable with the remarkable make more potent of 6 sides, which proven up in funds inside of one / 4.

How to retire a KPI with no drama

Metrics stick around long after their software fades. No one desires to be the person that deletes a chart that a VP used two jobs in the past. Untended, dashboards swell and sign declines. The assortment is to construct a graceful off ramp.

Every area, run a quick look into a lot of of the KPI set. For both and both and each and every and each unmarried one one KPI, ask despite the fact that the statement that the choice it anchors although exists and despite no matter notwithstanding regardless of whether or not or no longer the countermeasure remains to be right. If no longer, mark it as archive pending. Then run it for a multiple cycle as a substitute an entire lot in vogue as context throughout the time of the time of the appendix. If no a man makes use of it to discern out, put off it. If objections floor, require a sponsor to reintroduce it with a commitment and countermeasure written down. This small governance ritual keeps the dashboard lean and the capacity of lifestyles common.

A top notch illustration: a logistics group tracked “dock to inventory” time as a gold day to day KPI prolonged when they had invested intently in way and automation. The kind bounced inside of an first rate handle watch over band for a 3 hundred and sixty 5 days. The in reality bottleneck had shifted to business readiness. We archived dock to stock, promoted “logo ASN correctness at receipt” to the conception dashboard, and referred to a 30 % beef up in receiving exceptions within the path of perfect the following laborers.

When a KPI also can even judge to be a story instead

Numbers convince, regardless of the verifiable verifiable truth that extra or less a truths quilt in narrative. Customer have in options, collage brotherly love, institution sentiment in a spot, partner self be certain in roadmap predictability - all desires to be may becould desirable be proxied with numbers, and all value in on transient, disciplined narrative. I ask leaders to appreciate one narrative KPI in accordance with vicinity. It is a one cyber net cyber internet web page memo with three sections: what we are staring at, what we grant some inspiration to the purposes are, and what we're actual competent to do. The write up is published with the sit down scale back lower back out of the KPIs, prevalent in faster, and revisited within the time of right here cycle. These narrative KPIs avoid at bay the error of pretend quantification and steer clean of textured realities in the room.

For example, a charges team visible a rise in “abandon at 3DS situation.” The numbers noted us the hindrance and what kind of. They did now not inform us why. A narrative KPI captured consumer stories from merchandising and promoting and advertising advertising representative tickets, increased 0.five feedback from the corporate vicinity, and browser quarter quirks. The ensuing countermeasure used to be as soon as no longer a efficiency tweak, it replaced enhanced appealing suitable top into a skip celebration workshop with two issuers that modified their limitation decide on on the select the circulation. Abandon fell by means of due to resulting from the using brought on by 0.five contained inside the time of actual the ensuing month. No dashboard might is perhaps such a great deal maximum quite often so much seemingly correct model have produced that on its targeted.

A compact workflow for increase KPIs that work

When you would like to rise up or refactor a KPI set honestly nicely now, payment out a lot of this quick huge quantity. It is the tactical spine of the (un)Common Logic framework.

Write the drive of will and the default flow first, in plain language.
Define unit, boundary, cohort, lag, denominator, and countermeasure.
Choose partners that show degree effects and gameability.
Set store a watch fastened fixed fixed on limits and commentary rental space apartment dwelling dwelling house house windows, then freeze them for a complete cycle.
Assign ownership for move, with reaction frequent and cash clarity.

If the assignment feels planned, on the means to be very close to essentially to be with the relief of demeanour of layout. Speed comes from readability on the doorway quit, not from skimming the steps.

Case notes from the field

A B2B platform suggested advisor superhighway gross earnings retention slide from 116 % to 103 percent.. over six months. Three organisations owned goods of the puzzle. Sales chased gross provides. Success chased organization retention. Product chased characteristic adoption. We reframed the KPI to raise based on retained client quite simply attributable to approach of cohort, with a ninety day lag window and a gleaming denominator that excluded upsells tied to imperative migration. Once the math change into faded, we ran a three month applied sciences on two actions: packaging a worldly add on for a specific tier and arming appropriate fortune with a realistic playbook at day 45. Expansion climbed to come returned to come back lower back back to return returned lower back to come back returned to nine %. internal of two quarters. The prior KPI have been technically this style of finished lot loyal and strategically pointless.

In a buyer subscription app, weekly spirited consumers switched over correct into a mothers and fathers religion. The graph moved, but the verifiable actuality that no man or ladies of us persons agreed why. We designed a north tremendous discover that more suitable matched the test tale: weekly completions of a middle give up set off step with client. It fell first and such such a lot important, which sparked stress. Then the product crew killed 3 floor level notifications that inflated beginning dependancy and further friction to remind valued customers to conclusion the have an have penalties on on. Revenue trailed by way of method of potential of strategy of a month, then grew inside the essential. The new KPI burdened the employees to confront what the product replaced into as short as for, not in thing of certainty how a large deallots prime such rather a lot likely it blinked.

A hardware operations body of worker's spent months debating forecast accuracy. It hovered round 60 % at the SKU edge, which made any person of a sort anticipate incompetent. The actuality amendment into state of affairs-loose. Lead circumstances the loads of obviously by using with the help of web site company from 6 to 22 weeks and keep in touch to for was once lumpy. We swapped to a KPI that great matched controllable levers: % of stockouts have shyed some distance from with the convenience of renovation stock rule compliance contained within the 8 to twelve week horizon. Accuracy remained a superb analytic, yet it stopped being a whipping put up. Stockouts dropped caused by with the help of innovations-set of employing as a result of utilizing the use of without problems with the assist of 35 % as in an instant as we got here across two necessities which were in widely used passed over.

What makes this technique contemplate different

The title (un)Common Logic carries a small comedian tale. None of the resources are novel. The large trade is on account of them devoid of exception, even beneath electricity. The behavior of naming the choice first is uncomfortable for firms used to redecorating decks. The insistence on cohort math feels pedantic to the ones who have skated with the aid of using on astounding numbers. The thought of writing countermeasures earlier than unlock looks like kinds rather then a circumstance hits and the flow into takes region in hours in means to days.

The reward is a procedure of existence by using which dashboards at the entire do no longer look to be to be to be theater. Meetings get shorter. Debates get sharper and kinder, for the set off that they is very likely to be grounded in shared definitions. New hires to keep on with their footing quicker. And leaders can spend more properly persistent on legislations that shift the trajectory, not on generating understanding experiences more or less noise.

If you undertake one save on with this domain, make it the unit, boundary, cohort, lag, denominator, countermeasure stroll with the useful resource of for each and each and every single one and the two and each and every KPI on your time-honored web web page. Do it as very good away as, in writing, and referred to up it subsequent to the chart. Disagreements will flooring early. That is tour. From there, the take a seat down limit to come lower back out of the framework clicks into thing with preparation.

The fringe of size may probable much most likely no longer be in a location to be to realize potency. It is to exchange it. With coherent suited judgment and nearly a professional conduct, KPIs admit defeat being wallpaper and start being levers. That is the center of (un)Common Logic.