This study offers a comprehensive assessment of corruption as experienced by businesses in the western Balkans, based on interviews with more than 12,700 companies. If not countered by strong preventive and law enforcement action, corruption and crime can act as a barrier to private and foreign investment as well as trade, and hinder economic development. By identifying areas of vulnerability, the study aims to support governments in the region to implement the United Nations Convention against Corruption and work effectively with the private sector to develop and put into action anti-corruption strategies and measures.