This book constitutes the refereed proceedings of the 9th International Conference on Tests and Proofs, TAP 2015, held in L` Aquila, Italy, in July 2015, as part of the STAF 2015 Federated Conferences. The 11 revised full papers and 1 short papers presented together with 3 invited talks were carefully reviewed and selected from 21 submissions.

Abstracts of Invited Talks.- Testing, Fixing and Proving with Contracts.- Mind the Gap: At the Crossroads of Design, Implementation and Foundations.- Reasoning about C Concurrency and Compilers.- Accepted Papers.- Scalable incremental test-case generation from large behavior models.- Test Case Generation for Concurrent Systems Using Event Structures.- Fast Model-Based Fault Localisation with Test Suites.- Case Study: Automatic test case generation for a secure cache Implementation.- Verifying Code Generation Tools for the B-Method Using Tests: a Case Study.- Software Validation via Model Animation.- Sequential generation of structured arrays and its deductive verification.- Checking UML and OCL Model Consistency: An Experience Report on a Middle-Sized Case Study.- A constraint optimization model for analysis of telecommunication protocol logs.- Experimental Evaluation of a Novel Equivalence Class Partition Testing Strategy.- Testing Functional Requirements in UML Activity Diagrams.- Coverage of OCL Operation Specifications and Invariants.