This article focuses on the interactions between state and community mechanisms in the design and delivery of a titling program and a land market reform in rural Mexico. Whereas the titling program did provide a greater sense of tenure security among landholders, legalizing transactions has unexpectedly generated an informal land market, resulting in tenure insecurity for the corresponding buyers. These contrasting outcomes are not a matter of technical failure, unaffordable fees or rent seeking. Rather, they can be traced back to differentiated processes of policy delivery by the administration officials, with regard to acknowledging prevailing local institutions and managing local information.