To test whether the International Diabetes Federation - Western Pacific Region (IDF-WPR) Guidelines are more effective than standard practices in primary care (general practitioner) clinics for the management of type 2 diabetes mellitus (T2DM) in Asia. A 12-month multinational multicentre prospective cluster randomisation clinical trial within a primary care setting, with 2 parallel treatment arms: diabetes management using IDF-WPR guidelines versus standard clinic practices. 400 subjects will be recruited from 100 sites (4 subjects per site) in ten Asian countries (China, Hong Kong, Indonesia, Korea, Malaysia, Philippines, Singapore, Taiwan, Thailand and Vietnam).