The relationship between big city mayors and the federal government has evolved as Canada's largest cities increasingly seek direct engagement with Ottawa on issues affecting urban areas. Constitutionally, municipalities are provincial responsibilities, but major cities argue that federal policies on immigration, infrastructure, housing, and climate significantly impact them, warranting direct dialogue. Federal programs like the Canada Infrastructure Bank and housing initiatives involve federal-municipal cooperation. Provincial governments sometimes resist this direct relationship, viewing it as bypassing provincial jurisdiction. The tension reflects cities' growing importance and the limitations of constitutional arrangements designed when Canada was predominantly rural.