Type-2 diabetes is a common non-communicable disease, especially in developing countries like India, posing a huge economic burden on the family and nation as a whole. Traditionally fasting plasma glucose and OGTT is advocated for diagnosing type-2 diabetes, and HbA1c is often considered for monitoring. Very recently however HbA1c is proposed for diagnosis of HbA1c, acceptance of which is greatly debated. This article describes the evolution of HbA1c from the time of its discovery to the present status of a diagnostic test for type-2 diabetes. We observed that HbA1c has some major advantages over fasting plasma glucose estimation for diagnosing diabetes mellitus, although various biochemical and clinical factors act as a limitation. These limitations can be nullified very often, but the lack of laboratory standardization of method and the cost of testing limits its utility in India. But we conclude that HbA1c can be considered once effective cut off levels are established and laboratories are standardized, as the huge economic burden which diabetes pose in India over comes the cost of HbA1c testing in India.