This article has shown that empirical research evidence strongly supports the posited theoretical view that academic self-concept is multidimensional. It is comprised of two uncorrelated and distinctive facets namely, math academic self-concept and verbal academic self-concept. Research studies purporting to investigate the relation between academic achievement and academic self-concept must differentiate between subject-specific domains of the hypothetical second-order latent construct, academic self-concept. The conceptualised multidimensionality of academic self-concept is required to gain a comprehensive understanding of this particular self-concept facet, particularly its potential association with academic achievement. Additionally, it has been shown that individuals utilise two different processes of comparison. The external frame of reference is used to compare one's skill level with that of others' skill level (math and verbal domains); while the internal frame of reference is employed in comparing varying degrees of self-perceived skill levels. The internal/external frames of reference model has been put forward to explain the enigmatic associations between math and verbal achievement and math and verbal self-concept.