What is the difference between an obligation of result and an obligation of effort?

With a result obligation you must achieve the agreed outcome and missing it is itself a breach; with an effort obligation you owe diligent professional conduct and are judged on care, not outcome.

Who carries the burden of proof?

For a result obligation the creditor proves only that the result is absent; for an effort obligation the creditor must prove the debtor fell short of the required standard of care.

How is the obligation type determined if the contract is silent?

Courts look at the nature of the performance, the parties' intent, trade custom and whether a specific outcome was central to the agreement. Certain professions such as contractors in construction are presumed to owe a result; consultants and advisers are more often presumed to owe effort.

Can a supplier limit liability even if they owe an obligation of result?

Yes. A limitation-of-liability clause can cap exposure even when a result obligation is missed, provided the cap does not cover intent or gross negligence. The obligation type determines when a breach has occurred, not the size of the resulting claim.

Does the distinction matter in standard IT contracts?

Yes, significantly. Whether a software deliverable must pass defined acceptance tests (result) or merely be built with professional care (effort) affects both who proves breach and whether the client can dissolve without proving negligence.

Obligation of result

A duty to deliver a specific, agreed outcome, not merely to make a best effort.

Definición

An obligation of result binds a party to achieve a defined outcome; failure to reach that outcome is a breach in itself, regardless of effort applied. This contrasts with an obligation of effort (inspanningsverplichting), under which the debtor owes diligent, professional conduct and is not liable merely because the hoped-for result is not attained. The distinction is decisive for breach and burden of proof: with a result obligation the creditor need only show the outcome is absent, while with an effort obligation it must prove a lack of due care.

Ejemplo

A contractor who agrees to build a watertight roof owes an obligation of result; a consultant advising on strategy typically owes only an obligation of effort.

Por qué es un riesgo para la empresa

Misclassifying an obligation can undermine your entire claim. If a supplier describes their duty as mere effort when you expect a defined outcome, you may face an uphill proof battle when the result is missing. The risk is highest in IT and engineering contracts where deliverable quality is hard to measure without clear, documented acceptance criteria tied to the agreed outcome.

Cómo gestionarlo

Describe the deliverable with measurable criteria -- dimensions, performance thresholds, test pass rates -- so "result" has a concrete meaning.
Include an acceptance-test clause that triggers formal acceptance only when the criteria are met, creating a clear record of pass or fail.
Track milestones and deliverable statuses in one place so any failure to meet the agreed outcome is recorded with a date.
Review the contract wording before signing to confirm the obligation type matches the commercial intent -- amend vague "best efforts" language when a result is genuinely required.

Referencias legales

BW 6:74 Dutch Civil Code: breach of contract Derecho neerlandés

Salvo indicación en contrario, las referencias remiten al derecho neerlandés (Burgerlijk Wetboek, el Código Civil neerlandés); los instrumentos de la UE como el RGPD se aplican en toda la UE. Se trata de información general, no de asesoramiento legal. Otras jurisdicciones tratan estos conceptos de forma distinta. Verifique el texto vigente y su situación con un abogado cualificado.

Preguntas frecuentes

Preguntas comunes sobre este término.