Dr. Lowenthal is interested in the relationship between attempts to promote political democratization and market-oriented economic reforms throughout the world, especially in Latin America, East Asia and Central Europe; international influences (especially U.S. policy) on prospects for democratic governance; the state of democratic governance in Latin America and the Caribbean; Latin America's changing international role; policy issues in U.S.-Latin American relations; the international interests of the western region of the United States, and California's global role and relationships.

His major Publications include: The Dominican Intervention (1972, republished, 1995); Partners in Conflict: The United States and Latin America in the 1990s (1987; revised edition, 1991). Editor or co-editor of 12 books, most recently, Constructing Democratic Governance: Latin America in the Mid-1990s (1996), Latin America in a New World (1994), and The California-Mexico Connection (1993). He has published some 115 journal articles.

Lowenthal is the founding director of the Latin American Program at Woodrow Wilson Center and of the Inter-American Dialogue, the premier policy forum and think-tank on Western hemisphere affairs. He is also a member of the Council on Foreign Relations, Overseas Development Council, and the International Institute of Strategic Studies. Board member of the Pacific Council, InterAmerican Dialogue and Fulbright Association. Editorial board member of New Perspectives Quarterly, Hemisphere and Hemisfile. Lowenthal served on the Councils of the American Political Science Association, the Latin American Studies Association, the International Advisory Council of the Helen Kellogg Institute at Notre Dame, the Center for U.S.-Mexico Studies at the U.C. San Diego, and numerous other boards and committees, including the Board of the California-Mexico Fellowship Program and the Mayor's International Trade Advisory council for Los Angeles.