GGOS contributes to a number of GEO activities, in particular, some of the so-called Communities of Practice (CoP), which GEO has identified or established as its main interface to major user groups. Some of these CoPs developed out of Themes of the Integrated Global Observing Strategy-Partnership (IGOS-P), which has been terminated in May 2008 in the wake of the establishment of GEO. GGOS was a member of IGOS-P since 2006, and during this membership established relations to several of the Theme Teams, which now map into relationships to the corresponding CoPs.

Examples of these links are a GEO workshop on geohazards, which was joint workshop organized by GEO, GGOS, and the Geohazards CoP. With the Coastal Zone CoP, GGOS is also contributing to a series of Workshops. GGOS also established a IGCP Project with the goal to strengthen the aspect of GGOS as an observing system for the global Water cycle, and this project is coordinated with GEO and the Water CoP.