What constructivism might be for mathematics education

Once the conceptualizations on constructivism have been analised, their implicacions are studied from the point of view of the education of mathematics. Starting with examples and experiences, we approach issues and expressions in an attempt to answer questions such as: what does constructivism seem to be like?, what does it not seem to be? and what does it need to be? *Articulo preparado para la undcima reunin anual del Grupo Internacional para la Psicologia de la Educacin Matematica, Montreal, 19-25 Julio 1987. Agradecimientos a John Mason por sus comentarios en un previo borrador.