This chapter summarizes the evolution of Mexico-United States ties. It analyzes the increased breadth and assertiveness of contemporary Mexican foreign policy beyond the United States, recognizing that Mexico-United States relations are affected by this change. The chapter examines major, specific issues in contemporary Mexico-United States relations and highlights Mexico's deepened dependency on its neighbor in times of economic crisis. As the Mexican Revolution replaced political stability and friendliness to foreign investment with instability and nationalism, Mexico-United States relations predictably worsened. One could argue that Mexico has seen fit to become more active in Central American affairs precisely to achieve goals once assured with less active diplomacy. The Central American conflicts inevitably push many problems onto Mexico, and Mexico believes that it is better to assume an active role than passively to brace for the consequences of those problems.