This is a protocol for a Cochrane Review (intervention). The objectives are as follows:

To assess the effects of group-based self-management education for adults diagnosed with T2DM on clinical, lifestyle, and psychosocial outcomes in the short (six months to 10 months), medium (> 10 months up to 18 months), and long (> 18 months) term.

To explore the intervention characteristics and processes that are aligned with effective group-based self-management education for people with T2DM.