The formal organisation of science Olympiads in Mexico dates from 1987, when a national contest on Mathematics was held in order to identify a team to represent the country in the International Mathematics Olympiad. In 1991, the Mexican Academy of Sciences ("Academia Mexicana de Ciencias"-AMC) created the National Science Olympiads Program with the aim of spreading interest amongst Mexican youth and the general public about different scientific disciplines. Between 1991 and 1995, annual national contests in Mathematics, Physics, Biology and Chemistry aimed for high school (Grades 8-12), pre-university students aged 15 to 19, were organised and carried out by the AMC. From 1996, the Mathematics and Physics contests have been organised under the full responsibility of the Mexican Mathematical Society ("Sociedad Matematica Mexicana") and the Mexican Society of Physics ("Sociedad Mexicana de Fisica"), respectively. Since then, the AMC has continued organising the national contests in Biology and Chemistry as well as two annual contests in Mathematics aimed at 12-15-year-old students (Grades 6-9). Starting in 2003, the AMC has also organised the Mexican Geography Olympiad ("Olimpiada Mexicana de Geografia"-OMG). In all these cases, representative teams are selected to attend and compete in different international contests in the particular disciplines. Currently, the AMC is promoting the Mexican History Olympiad to be held for the first time during 2007. This paper presents a brief account of the origin, organisation, development and future challenges of the OMG. (Contains 3 tables and 2 figures.)