Treating severe and complex obesity requires specialist multi-professional teams for assessment, management and optimizing patients’ health outcomes. The aim of this study was to review existing evidence for defining commissioning and delivery of primary or secondary care weight assessment and management clinics to patients needing specialist care for severe and complex obesity. Twenty-two UK royal colleges and professional organizations were invited to develop the guidance revision according to the NICE-accreditation process. Fifty references were included in the final report. The following additions have been identified as new emergent developments to be included in the guidance: - multi-disciplinary team pathways for children/adolescent patients and their transition to adult care, and - anaesthetic assessment and recommendations for ongoing shared care with general practitioners, as a chronic disease management pathway. Authors indicate that the Guidance Development Group recommends the use of the NICE-accredited commissioning guidance as healthcare services in different countries develop services to manage patients with severe and complex obesity.