Massively multi-player online construction and management simulation video games *MMOCMS) are a form of massively multi-player online simulation video games in which players build, expand or manage fictional communities or projects with limited resources.

The player logs in few times per week, sets orders for the in-game team and find how to defeat human opponents and their strategies. One of the most popular MMOCMSs is Hattrick. Other management games require taking control of people such as The Sims Online, or the music managing game, Project Rockstar. MMOSS games can also possess aspects of the MMOCMS, depending upon the level of availability of the capability to build objects and buildings or manage establishments and organizations that is afforded to the user (usually a paying user).