Two articles that featured in HEJ's April and November 2013 issues focused, respectively, on the roles and responsibilities of those operating and managing medical gas pipeline systems, and on the MGPS Permit to Work System. In this third article in a four-part 'series' by the same author, experienced medical gas systems trainer, Geoff Dillow, who also has extensive expertise in project management, developing medical gas Operational Policies, and assessing medical gas system compliance, and co-authored HTM 02-01, explains how to raise and complete The MGPS Permit to Work.