The main objective of this study is to determine the efficacy, safety and utility of fully closed-loop glucose control in the home setting in adults with type 2 diabetes (T2D). This study builds on previous and on-going studies of closed-loop systems that have been performed in Cambridge in adults with type 2 diabetes in the inpatient and in the home setting and in children and adults with type 1 diabetes. This is an open-label, multi-national, multi-centre, randomised, single-period parallel study, involving a run-in period followed by a 26-week intervention period during which glucose levels will be controlled either by a fully closed-loop system or by participants usual insulin therapy with continuous glucose monitoring. A total of up to 224 adults with type 2 diabetes using insulin will be recruited through outpatient diabetes clinics, primary care centres, social media advertising and other established methods at participating centres. Participants will receive appropriate training in the safe use of the study devices. The primary outcome is the between group difference in HbA1c at 26 weeks. Other key outcomes include the time spent with glucose levels within, above and below the target glucose range (3.9-10.0mmol/L) and mean sensor glucose as recorded by CGM over the 26 weeks. Insulin requirements, body weight, renal and liver function will also be compared. Safety evaluation comprises severe hypoglycaemic episodes, and other adverse and serious adverse events. Human factors outcomes include CGM \& closed-loop usage, questionnaires and semi-structured interviews.