While much of this recent literature has focused on how the amount of insurance varies across different worker and employer groups, the role of collective bargaining has received somewhat less attention. 2 The scant evidence on collective bargaining is particularly surprising as the role of trade unions as an insurance device has long been emphasised by researchers. The general argument here is that union may mitigate the enforcement problems that arise within risk-sharing agreements between workers and their employers (., Horn and Svensson 1986, Malcolmson 1983). Clearly, examining the trade unions’ role in providing wage insurance is crucial to an understanding of how labour market institutions affect wage dynamics
