One of the more critical roles of the education system is to develop human capital. Low quality, unequal human capital development remains an important issue for Trinidad and Tobago as it seeks to align its economic structure with the emerging requirements of a knowledge society. The education system inherited from British colonial rule was noticeably elitist and examination-oriented, designed to filter, segregate and retain students based on perceived meritocracy, as defined solely by performance in public examinations. Significant features of this inherited differentiated system include segregated schools and embedded institutional practices and beliefs supportive of academic tracking, streaming and setting. Despite government?s commitment to a seamless system, the legitimacy of a differentiated system remains high among the populace, with a persistent concern for the fate of “the top 20% of the ability group”. The question then becomes, are the country’s needs (and that of all ability groups) best served by a differentiated or non-differentiated school system? In other words, is the current design of the education system the best strategy for efficient and equitable human resource-centred development? The issue of structure and outcome in education systems has emerged internationally with the growth of regional and international assessments, which allow comparisons and benchmarking across countries and education systems. High quality differentiated systems as in Germany can be compared with high quality non-differentiated systems as in Finland. Trinidad and Tobago is currently enrolled in the PIRLS and PISA international assessments, and benchmarking data is available from the 1990/1991 IEA study of reading at ages 9 and 14 and the 2006 PIRLS. We use this information along with data from national assessments to analyze, benchmark, and compare outcomes from the differentiated education system in Trinidad and Tobago.