The RAPD method appeared a decade ago as an alternative in genetic relationship studies. The technique generates polymorphic band patterns, produced by PCR using arbitrary DNA sequence primers. If total DNA is used, RAPD yields abundant information about the analyzed genome in a rapid and inexpensive way. This information may be used in various types of plant genetic studies, such as hybrid detection, intra and interspecific genetic variation, genetic identity establishment, somaclonal variation analysis and, when combined with other methods, it helps in the elaboration of genetic maps. However, there are some requisites for its correct application. A strict control of working conditions is demanded. Furthermore, due to the anonymous character of polymorphic bands and the difficulties for establishing homologies, it is also recommended to confine RAPD uses to the specific or infra specific levels. Comparisons based on genetic distance calculations are accepted provided they do not require parsimony analysis methods.