I present a model in which the employment contract includes severance payment as an instrument for achieving optimal separation between the firm and the worker. I show that the privately optimal severance payment from the model can replicate the level and the variation in actual severance payments (and notice periods) across OECD countries. I conduct a policy experiment in which the existing unemployment benefits are financed by a separation tax. Under this policy, the actual severance payments need to change only marginally in order to achieve socially optimal separation. Zdroj anotace: OKCZ - ANOTACE Z WEBU