The government-opposition scheme of a two-party system does not function that clearly in a multiparty system which is the case in Belgium. To examine to what extent the opposition parties in a multi-partysystem are functional for policymaking, the period 1965-1971 was chosen for Belgium, providing a complete scale of government and opposition parties.A content analysis of all political parties' platforms in 1965 permits to determine the policy objectives, classified in policy areas, so that at the end of the six years a survey could be made about the completely andpartly realised planks of the platforms according to government and opposition parties, according to the party-strength which was congruent with the duration of government participation. In Belgium a distinctioncan also be made between the traditional opposition parties and the nonelitist opposition parties, which during the given period were not accepted as possible government parties by the political elite. To obtain a correct evaluation of the realisations, the approach took successively into account the absolute number of platform-planks, the number of specific items of a party and the degree of importance andsocial repercussion of the distinct planks that could be realised.Although respectively for 6, 4 and 2 years in the government the CVP, the BSP and the PVV realise approximately the same number of planks. The non-elitist opposition party Volksunie realised a smaller butstill considerable number of objectives. So did also, but to a smaller extent the RW, KP and FDP. The interpretation of these results could be the loss of distinctiveness of the government-opposition scheme in amultiparty system, the elite-consensus in Belgium, the function of the «zweeppartij» strategy and the definition of the opposition in terms of action.