The use of small-scale biogas digesters among farmers and households in rural areas of developing countries is a well-known technology. The potential for biogas in these areas is probably much larger than presently exploited and therefore more knowledge on factors that may further the use of biogas is needed. The present study draws on data from two extensive surveys in the Mekong Delta with questionnaires of one hundred and two hundred respondents, respectively, and data collected from personal interviews in all cases. The empirical evidence shows that the technology is well known and if the purpose is to expand the use of biogas, financial instruments (like subsidies) are the most important to rely on. High investment costs are important for the biogas investment decision and subsequently information on the economic benefits of cheap biogas is an important topic to address.