Drug naïve patients will be treated with Metformin. Patients who have failed on Metformin or are intolerant of Metformin will be randomised to gliclazide, pioglitazone or sitagliptin. With the ability to capture patient data beyond 6 months via data linkage we will monitor time to treatment failure and therefore compare which of the 3 oral agents is the best therapy to use after Metformin in a cost efficient and "real world" RCT.