Presentado en la VI Conferencia Internacional de la Sociedad Internacional de Investigación del Tercer Sector (ISTR), 11 al 14 de julio de 2004, Toronto, Canadá. There are a number of widely held assumptions about philanthropy in Mexico. One is that Mexican donors favor traditional charities and culture, rather than more controversial issues such as human rights or public policy analysis. Another is that the foreign donors who have supported these latter fields are now leaving Mexico in favor of poorer nations. Although anecdotes support these assumptions, they have not been treated as hypotheses to be tested against empirical evidence. One reason that this kind of empirical analysis has been so rare is the difficulty of obtaining reliable data, especially from governmental sources. The availability of data from government sources is slowly beginning to improve. The two most official sources of data are the Mexican Treasury Department (Hacienda) and the government’s Institute for Social Development (INDESOL). Each have database that offers a glimpse at the field through a particular lens: the former provides a list of organizations eligible to receive tax deductible donations and the latter has an information system based upon a census taken in 2000. Neither one provides data on levels and sources of funding. This paper will explore why this is the case and what this lack of systematic information implies about the sector in Mexico.