Objective: Little is known about why PwD leave traditional pathways and turn to DIY technology. This study aims to examine the motivations of Do-it-Yourself Artificial Pancreas System (DIYAPS) users and caregivers to build and maintain these systems. Methods: An online survey with 34 items was distributed to DIYAPS users and caregivers of children with DIYAPS through Facebook (“Looped” and regional subgroups) and Twitter (Diabetes Online Community). Results: 1058 participants from 34 countries responded to the survey. The majority were adult users (80.2%; 43% female; median age 41 years) with T1D (98.9%) for 25.2 years ±13.3. 19.8% were caregivers of children (47.4% female; median age 10 years) with T1D (99.4%) for 5.1 years ±3.9. With 10.1m ±17.6 on DIYAPS, HbA1c improved from 7.07% ±1.07 to 6.24% ±0.68 %. Time in Range improved from 63.21% ±16.27 to 83.07% ±10.11. Additional out-of-pocket costs of 712 USD/year were spent. Motivations to build a DIYAPS are shown in Fig.1. Conclusions: Improved glycemic control, need for an ‘autopilot’ and less acute and long-term complications were key motivations in both groups; as well as better sleep for caregivers. Users were also able to access and afford the required tools. These results may provide a better understanding of unmet needs of PwD and current challenges to uptake, in order to facilitate the involvement of patient-led and open source approaches in healthcare. Disclosure K. Braune: Advisory Panel; Self; Medtronic MiniMed, Inc. Speaker’s Bureau; Self; Dexcom, Inc. S. O’Donnell: None. B. Cleal: None. D.M. Lewis: Consultant; Self; Diabeloop SA, Roche Diabetes Care. A. Tappe: Consultant; Self; IME-DC GmbH. Employee; Self; Hi.health, Gruber-Debong GmbH. Speaker’s Bureau; Self; Dexcom, Inc., Roche Diabetes Care, Ypsomed AG. Other Relationship; Self; SOOIL Developments Co., Ltd. B. Hauck: Consultant; Self; Bayer AG, Eli Lilly and Company, LifeScan, Inc., Novo Nordisk A/S, Roche Diabetes Care, Roche Pharma. I. Willaing: None. R. Scibilia: Speaker’s Bureau; Self; Roche Diabetes Care. E. Rowley: None. W. Ko: None. G. Doyle: None. T.C. Skinner: None. K. Raile: Advisory Panel; Self; Abbott, Lilly Diabetes. Funding European Union