In current design practice synthesis tools play a key role, letting designers to concentrate on the specificationof the system being designed by carrying out repetitive tasks such as architecture synthesis and technology mapping. However, in the new design flow, validation still remains a challenge: while new technologies based on formal verification are only marginally accepted for large designs, standard techniques based on simulation are beginning to fall behind the increased system complexity. This paper proposes an approach to simulation-based validation, in which an evolutionaryalgorithmcomputesuseful input sequences to be included in the test bench. The feasibility of the proposed approach is assessed with a preliminary implementation of the proposed algorithm. Keywords Simulation-basedvalidation,GeneticAlgorithm.