The increasing participation of older people in tourist activities, combined with a demographic phenomenon that implies the aging of the world population, made governments and tourism providers in developed regions identify senior market as a priority. Tourism is a multidimensional activity that have increased substantially in the last years, challenging the destinations' ecosystems since tourism contributes to greenhouse gas emissions globally. Mass tourism has a significant impact on the environment; hence, sustainable tourism pops out in such circumstances. To the theme of sustainability, Mexico deals with important contrasts. This research outlines the main elements that tourism marketing (MT) could contribute in terms of sustainability as a competitive advantage of a destination that serves the international senior tourist segment, from the perspective of two case studies of sun-and beach tourist destinations in northwestern Mexico.