The article describes the political crises of June and October 1978 in Belgium. For reasons connected with time and space, this contribution ends with the formation of the Vanden Boeynants transition-government, although even with the formation of the Martens-cabinet in April 1979the problems are not yet solved. The formation of this cabinet has been a long-drawn effort, hampered by substantial obstacles, that have been present since June 1978: the difficulties to elaborate both a crisis-management-policy and a consensus concerning a new constitution. Moreover, all this remains overshadowed by fear and distrust from the other political parties towards de Flemish christian-democrats, who usually succeeded in keeping their internal quarrels a really inside affair. The crisis of 1978 has proved on the other side, that the Egmont-Stuyvenberg agreement on the federalisation of Belgium was neither well-balanced nor mature.