Observational reports suggest extended dialysis hours are associated with improved outcomes. These findings are confounded by better prognostic characteristics among people practising extended hours. The aim of this article is to provide an overview of the methods and baseline characteristics for ACTIVE Dialysis Study participants. METHODS: This multicentre, randomized, open-label, blinded endpoint-assessment trial randomized participants receiving maintenance haemodialysis therapy to either extended (=24?h) or standard (12-18?h) weekly haemodialysis for 12 months. A web-based randomization system used minimization to ensure balanced allocation across regions, dialysis setting and dialysis vintage. The primary outcome is the change in quality of life over 12 months of study treatment assessed by EQ-5D. Secondary outcomes include change in left ventricular mass index assessed by magnetic resonance imaging and safety outcomes including dialysis access events. RESULTS: A total of 200 participants were recruited between 2009 and 2013 from Australia (29.0 ), China (62.0 ), Canada (5.5 ) and New Zealand (3.5 ). Participants had a mean age of 52 (??12) years and 11.5 were dialysing at home, with a mean duration of 13.9?h per week over a median of three sessions. At baseline, 32.5 had a history of cardiovascular disease and 36.5 had diabetes. CONCLUSION: The ACTIVE Dialysis Study has met its planned recruitment target. The participant population are drawn from a range of health service settings in a global context. The study will contribute important evidence on the benefits and harms of extending weekly dialysis hours. The trial is registered at clinicaltrials.gov (NCT00649298).