Towards the end of the 1990s, a perplexing situation occurred in two large North American cities. In Toronto, Ontario, and Los Angeles, California, conservative political forces undertook to restructure the system of urban governance. While initiated by conservatives in both cases, in Toronto the result was consolidation; in Los Angeles secessionism is rampant. In both cases the political debate on amalgamation and secession is tied in with discourses on size, efficiency and form of urban government. In both cases, also, the shift from government to governance has been a central theme. This article investigates how local governance has changed in these two cities by comparing historical traditions of governance. Each city has a specific set of external relationships with other geographical and political scales and a set of characteristic internal contradictions. Internally, Los Angeles’ tradition of splintered governance stands in contrast to Toronto’s metropolitan governance model. Amalgamation and secession have been introduced as strategic options of governance restructuring in both cities in the late 1990s. Both (projected and realized) scalar changes of governance processes and institutions have been accompanied and characterized by social struggles and widespread political debate. The article outlines these debates and discusses the respective political alliances which have formed in both urban regions on the issue of amalgamation/secession.