OCTA's members are involved in locating the exact emigrant trails, and protecting, marking and mapping the trails. OCTA works to have these trails designated by Congress as National Historic Trails. Research of the trails is promoted and education about the trails is encouraged.
Members also take part in collecting data from overland documents for a database.
The COED program is the Census of Overland Emigrant Documents. OCTA's headquarters is in Independence, Missouri, home of the original jumpoff to the emigrant trails. The Merrill J. Mattes Research Library, located in the National Frontier Trails Center adjacent to OCTA Headquarters, is maintained and open to the public for trails study. The organization publishes, on a quarterly basis, the Overland Journal magazine, containing articles and book reviews, and News From the Plains, a newsletter of national and chapter activities. Other Chapter information is not yet available for Nebraska, Idaho-Montana and Colorado.