This study develops a search and matching model for labour markets with temporary and permanent contracts. It matches empirical patterns of higher matching rates and lower surplus for temporary workers and predicts an increase in separation taxes leads to a fall in the number of new permanent jobs, an increase in their wages, and stable separation rates because temporary workers shield permanent workers from adverse shocks. We find empirical support using a regional French policy experiment, the “Contrat de Transition Professionelle”, which increased separation taxes for recently hired permanent workers in firms with fewer than 1,000 workers.

This paper introduces strong complementarities in labour into an otherwise classical Diamond-Mortensen-Pissarides search model. Specifically, two workers are required to perform a task. The assumption of Nash bargaining is maintained to represent the Hosios condition transparently. We show that this setup leads to additional externalities that require more than a Hosios-style condition to be met. The surplus must be shared between the workers so that the employer internalizes additional externalities. This makes implementing efficiency even more challenging.

This paper investigates on a theoretical level the underlying causes of recent trends in decision of firms to hire temporary and permanent labour when workers and firms meet through a frictional directed search technology. Temporary workers differ from permanent workers in that they have a lower bargaining weight but look for a permanent job while on the temporary job. The findings are that permanent arrangements are more prevalent the more productive the aggregate production function is, i.e. also in the less productive phases. More efficient matching has an inverse U shaped impact, it first increases the prevalence of temporary arrangements and then decreases it. Bargaining weights have an ambiguous impact.