ABSTRACT. Market intermediaries play important roles in the development of tropical-forest frontiers but are often overlooked in the assessment of land-change dynamics. Consistent with research beyond land-change studies, intermediaries are found to be a pivotal element in land-use and land-cover change in southeastern Mexico. They have stimulated commercial chili cultivation in this development frontier, providing transportation and other services to smallholders who could otherwise not enter the chili market. This role comes at the cost of a near monopoly on chili marketing. The various roles played by these intermediaries, or coyotes, the means by which they operate, and the consequences for smallholders and land use are detailed for the Calakmul Municipality, Campeche, Mexico.