Rodent, (order Rodentia), any of more than 2,050 living species of mammals characterized by upper and lower pairs of ever-growing rootless incisor teeth. Rodents are the largest group of mammals, constituting almost half the class Mammalia's approximately 4,660 species. In 1994, we believed that examples of long-term successes in reducing rodent damage to tropical crops were very limited. At the time, the situation was blamed on insufficient information that had, over previous decades, precluded specific recommendations.Beginning in the late 1960s, several research projects, primarily focused in Asia, investigated important crop loss situations and demonstrated several effective rodent-control methods.Moreover, these findings and some control recommendations were published and incorporated into extension programmes in a number of areas. Most of the publications concerned were in widely available 'grey literature' or in conference proceedings because few journals were available with an interest in applied vertebrate pest control research - and even those were not available to managers, researchers or extension personnel in problem areas.