¹ Observatorio Astronómico, Universidad de Valencia, 46100 Burjassot, Spain
² GEPI/FRE K2459 du CNRS, Observatoire de Paris, 92195 Meudon, France

We present a photometric survey aimed to characterize the Be star population of young open clusters. It is found that in these clusters early-type Be stars are more frequent than in the galactic field, and late-type Be stars are scarce or inexistent. We interpret this result as evidence for an evolutionary enhancement of the Be phenomenon towards the end of the main sequence lifetime.

In Interplay between periodic, cyclic and stochastic variability in selected areas of the H-R diagram, ed. C. Sterken, ASP Conf. Series, in press.
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