The SouthEast Atlantic Coastal Ocean Observing System (SEA-COOS, www.seacoos.org) is a regional partnership that has initiated an integrated coastal ocean observing system for a four-state (North Carolina, South Carolina, Georgia, and Florida) region of the southeast coastal United States. The long-term intent of SEA-COOS is to establish a regional coastal ocean observing system that will be part of the coastal component of the national Integrated Ocean Observing System (IOOS) envisioned by Ocean.US. SEA-COOS was initiated in September, 2002 with funding from the Office of Naval Research (ONR) as a coordinating and enhancing effort between several existing subregional-scale efforts in the southeast, the Sea Grant Offices from the four states, and a number of federal agencies. This article briefly describes the essential elements of an observing system, the region-wide observations, overlapping circulation models, data management capabilities, and outreach and education activities of SEA-COOS, at present and planned for the coming year. Development of a governance system has also been pursued, and an initial structure is in place for SEA-COOS.