The CMS experiment is about to embark on its first physics run at the LHC. To maximize the effectiveness of physicists and technical experts at CERN and worldwide and to facilitate their communications, CMS has established several dedicated and inter-connected operations and monitoring centers. These include a traditional โControl Roomโ at the CMS site in France, a โCMS Centreโ for up to fifty people on the CERN main site in Switzerland, and remote operations centers, such as the โLHC@FNALโ center at Fermilab. We describe how this system of centers coherently supports the following activities: (1) CMS data quality monitoring, prompt sub-detector calibrations, and time-critical data analysis of express-line and calibration streams; and (2) operation of the CMS computing systems for processing, storage and distribution of real CMS data and simulated data, both at CERN and at offsite centers. We describe the physical infrastructure that has been established, the computing and software systems, the operations model, and the communications systems that are necessary to make such a distributed system coherent and effective.