This research is a survey of unregistered businesses conducted in Cambodia between February 2012 and February 2013 as part of Cambodia Enterprise Survey 2012. 303 informal businesses were interviewed. Cambodia Enterprise Survey 2012 (also known as Investment Climate Survey 2012) was conducted by the World Bank Cambodia country office and Asian Development Bank. The survey formed analytical background for the Investment Climate Assessment (ICA) prepared by the World Bank in partnership with the government of Cambodia. The assessment was completed in August 2014. The objectives of the 2014 Cambodia ICA are to provide up-to-date and fact-based analysis of the business environment for development partners, policymakers in the government, private sector, civil society, and outline priorities for improving business environment and suggest possible policy options for achieving them. Cambodia Enterprise Survey and Cambodia Informal Survey follow the same methodology, the only difference between them is a formal status of interviewed establishments: the dataset for Cambodia Enterprise Survey (also published in Microdata Library) only includes firms registered with the Ministry of Commerce and dataset for Informal Survey includes businesses not registered with the Ministry of Commerce. Cambodia Enterprise Survey was not conducted under the supervision of World Bank's Enterprise Analysis Unit, as other Enterprise Surveys, and therefore small variations in methodology are present. Stratified random sampling was used to select the surveyed businesses. Data was collected using face-to-face interviews. The topics covered include firm characteristics, access to finance, sales, costs of inputs/labor, workforce composition, bribery, licensing, infrastructure, trade, crime, competition, capacity utilization, land and permits, taxation, informality, business-government relations, innovation and technology, and performance measures.