This article uses psychological contract theory to explore the consequences of
job insecurity among union members. We hypothesize that the perception of job
insecurity will correlate with a lower level of perceived union support and a
higher intention to resign union membership. We also test whether the
relationship between job insecurity and membership turnover is mediated by (a
lack of) perceived union support. In Belgium, Italy and the Netherlands, an
association is found between job insecurity and a reduction in perceived union
support, and between job insecurity and the intention to resign membership; this
association is also fully mediated by (a lack of) perceived union support. None
of these hypotheses are corroborated in Sweden. We discuss implications of these
findings for future research and for unions in Europe.