sion service, as well as NGOs and others that provide agricultural advisory services through special projects, continued to operate in the same areas as the NAADS program and elsewhere. This is likely to cause overattribution of the estimated effects to the NAADS program, particularly where NAADS par- ticipants also benefited from other extension services, as was likely the result in Benin et al. (2011). Besides addressing this shortcoming, it will be useful for a follow-up to this study to look at the costs and benefits of investment in the program and assess the returns to such investment.