A meeting point for scholars working on the processes of formation of coalition governments in European parliamentary systems is the analysis of the Spanish case. Since the restoration of democracy in the late 1970s parliamentary minority has not come to form any coalition government. Instead of it there have been parliamentary negotiation processes, in which stable parliamentary agreements have been reached to ensure continuous support for the government in office. One point worth noting is that, in these negotiations, the main national parties – UCD, PSOE or PP – have chosen to negotiate only with nationalist parties or non-state-wide parties. This article attempts, in the light of spatial analysis, to provide new arguments for understanding such negotiation processes.