Ten months after a devastating earthquake on January 12, 2010, cholera appeared in Haiti for the first time in nearly a century. The secretary-general of the United Nations formed an independent panel to "investigate and seek to determine the source of the 2010 cholera outbreak in Haiti." To fulfill this mandate, concurrent epidemiological, water and sanitation, and analysis of molecular investigations were carried out. Our findings indicated that the 2010 Haiti cholera outbreak was caused by bacteria introduced to Haiti as a result of human activity, specifically, by contamination of the Meye tributary system of the Artibonite River by a pathogenic strain of current South Asian Vibrio cholerae. Recommendations were presented to assist in preventing the future introduction and spread of cholera. The use of concurrent epidemiological, water and sanitation, and molecular analysis is recommended to public health professionals for future cholera investigations.