The forms of market competition define prices. The pharmaceutical market contains submarkets with different levels of competition; on the one hand are the innovating products with patents, and on the other, generic products with or without trade names. Innovating medicines generally have monopolistic prices, but when the patents expire prices drop because of competition from therapeutic alternatives. The trade name makes it easier to maintain monopolistic prices. In Mexico, medicine prices in the private market are high--according to aggregated estimates and prices for specific medicines--which reflect the limitations of pharmaceutical market competition and the power of the trade name. The public segment enjoys competitive prices using the WHO strategy for essential medicines on the basis of the Essential List.