Different from traditional gift exchange experiments, we study a field experiment where a random subsample of participants in the Swiss Labor Force Survey was sent vouchers to be used in adult training courses. Importantly for our purposes, actual voucher redemption can be traced. This gives the...

Workers will not pay for general on-the-job training if contracts are not enforceable. Firms may if there are mobility frictions. Private information about worker productivities, however, prevents workers who quit receiving their marginal products elsewhere. Their new employers then receive...