This paper has attempted to outline some basic aspects of Piaget's theory and place them in cross-cultural perspective. Several questions concerning approaches and the relevance of cross-cultural research for classification of Piagetian theory were discussed: (1) What types of questions within Piagetian theory are amenable to cross-cultural research? (2) How well can Piagetian studies help determine the importance of and differentiate between the factors affecting mental development? (3) Of what practical significance is cross-cultural Piagetian research? and (4) What types of research within the Piagetian framework might be helpful in the future? It was concluded that although a great deal of information has been gained from cross-cultural investigations, many critical research questions are still outstanding. (Author/CS)