Precondition
A precondition is a condition that must be satisfied before a test case or operation can be executed successfully.
“The required state of a test item and its test environment prior to test execution.”
(Definition reproduced from the ISTQB Glossary. Copyright belongs to ISTQB.)
View the complete ISTQB GlossaryWhat is Precondition?
Preconditions ensure that required data, configurations, permissions, or system states exist before testing begins.
Initial state: Defines required setup before execution.
Consistency: Ensures repeatable test execution.
Preparation: Reduces false failures caused by incorrect environments.
Real World Example
A travel platform is changing its refund policy for cancelled flights, with different outcomes depending on ticket type, cancellation time, loyalty status, and airline disruption reason.
No single happy-path test can cover the combinations. Precondition helps the tester see which conditions must be varied together and which outcomes should result.
The tester maps the policy into compact rules, removes impossible combinations, and designs cases that prove each meaningful refund decision is handled correctly.
The team avoids contradictory refund behavior because Precondition makes hidden rule combinations visible before customers start cancelling trips.
Practice Questions
Question 1
Which statement BEST describes Precondition in the context of ISTQB terminology?
Question 2
A tester needs to explain Precondition to a non‑technical stakeholder. Which approach is MOST appropriate?
Test your knowledge with real ISTQB-style questions
You’ve learned Precondition. Test your understanding with topic-specific questions in our Mock Exams.