The historical archive of global ocean subsurface temperature contains a large proportion of poorly quality-controlled as well as biased data. As a result, efforts to analyze past ocean change and variability are confounded, as is the use of ocean data assimilation systems. Currently many data centers perform automated ‘quick and dirty QC’ – redoing the same job poorly many times around the world. There have been no previous efforts to form a clean and definitive and very much needed historical archive. No single group has the manpower and resources to do the job properly – thus international cooperation is needed. The IQuOD 5th Workshop goals are to: provide an overview of what has been completed as part of IQuOD interim product v0.1 and discuss what went well and what could be improved (e.g., integrity checks, traceability, roadblocks, etc) • To review/discuss task teams plans beyond v0.1 and workout a draft plan/timeline (to note roadblocks and resources required to overcome them) • To start planning for training/outreach activities • To plan for dissemination/feedback strategies for IQuOD datasets/related products. ; Published ; Non Refereed