This is a rather complete, up-to-date review of Ethnomathematics. The author goes through a careful analysis of the main theoretical works on Ethnomathematics, specifically a detailed presentation of the directions proposed by Marcia Ascher, Paulus Gerdes and the reviewer. Then he presents his own definition of Ethnomathematics: ``a research programme of the way in which cultural groups understand, articulate and use the concepts and practices which we describe as mathematical, whether or not the cultural group has a concept of mathematics.'' Two terms are key in his definition of ethnomathematics: mathematics, and the author identifies it with what is done in schools, universities and by professional mathematicians around the world; and mathematical, which are those concepts and practices which are identified as being related in some way to mathematics. The reference is thus Western mathematics. Then the author proceeds to an important discussion on the universal/relative dichotomy that underlies much of the philosophy of mathematics. He proposes and leaves for a future paper the fundamental question of the interaction between [school or academics] mathematics and ethnomathematics. The author then uses two examples, triple weaving and sports statistics, to illustrate his definition and the resultant description of ethnomathematics.