Critical questions in educational psychology research to be addressed in this paper concern the casual relationship between academic self-concept, academic motivation and its effect on academic achievement. Do changes in academic self-concept and academic motivation lead to changes in subsequent academic achievement? Various studies have attempted to answer this question by examining the causal relations between academic self-concept and academic achievement as well as academic motivation and academic achievement. Less integral to research however has been the investigation of the relationship between both academic self-concept and academic motivation and their combined effects on academic achievement. For this reason, this paper aims to elucidate further the relationships among self-concept, motivation and academic achievement by proposing a longitudinal design by which self-concept and motivation are measured from a multidimensional perspective. The theoretical and practical implications of this important question will be discussed. (Contains 1 footnote and 1 figure.)