This is a research paper presented at the 55the annual National Reading Conference, Miami, FL. in 2005. The study examines levels of congruence between the Mexico’s National Reading Program (MNRP) first-grade curriculum and teachers’ theoretical orientation to reading instruction and their ability to articulate the program’s theorical foundation. The population included 242 elementary teachers. Data suggest that Mexican teachers are balanced in their approach to reading instruction with overall agreement with constructivist theory. Classroom observations identified high versus low implementers of the program guidelines