How will profoundly different national industrial relations systems react to the unification of market regulations within the European Community ? Labour unions have to deal with competition for jobs among workers in regions that are at different stages of industrial development. They must define a common programme which can foster convergence of interests which are in fact partially contradictory. Generally, the environment surrounding unions is unfavorable and unstable ; in many cases, membership is declining ; traditional alliances with other groups are breaking down ; it is hard to elicit support from governments that are preoccupied by improving competitivity without provoking inflation. Within this uncertain European Community context, where a complex redistribution of power is taking place, unions have to create a new basis for legitimacy, find new modes of organisation and strengthen their capacities for pursuing autonomous strategies.