The Southern Texas Archaeological Association was formed on December 2, 1973, in San Antonio at a meeting of forty charter members. The purpose of the organization was to promote the study of prehistoric and historic archeology in southern and south central Texas. At the founding meeting, it was agreed that the association would issue a newsletter, meet on a quarterly basis, and carry out such archeological activities as survey, salvage, and problem-oriented studies. Membership was open to both avocational and professional archeologists; subsequent membership forms contained an ethics statement in which members promised not to engage in the buying or selling of artifacts or to carry out untrained digging at sites. The STAA was administered by a chairman, secretary, treasurer, and editor (the office of vice chairman was formed in 1978). A membership coordinator worked toward recruiting new members, and an STAA Lending Library was established and overseen for many years by Edward Harris. The STAA founders included many long-time avocational archeologists and professional archeologists who had worked in South Texas archeology for many years. There was a close bond with the new University of Texas at San Antonio, and many of the quarterly meetings have been hosted by the Center for Archaeological Research at that institution. In addition, archeology faculty, staff, and students were active in STAA meetings and in overall development of the association. By the end of 1974 there were 270 members of the Southern Texas Archaeological Association; in September 1995 about 500 individuals and families belonged to the organization. Publication of the STAA newsletter, La Tierra, was initiated in January 1974, edited by T. C. Hill, Jr., of Crystal City, Texas. It quickly grew in content and developed into the organization's quarterly journal; later editors were Anne Fox (1976–78), J. L. Mitchell (1978–88) and Evelyn Lewis (1988–95). Papers published in La Tierra have focused on the prehistory and historic archeology (especially the Spanish missions) of South Texas and adjacent areas. Occasional papers on Central Texas archeology, Maya archeology, archeological methods, and other topics are published. In 1986 Thomas R. Hester initiated, in each issue, "Notes on South Texas Archaeology," presenting the results of a variety of research efforts. In 1975 the STAA began issuing Newsletter eight times a year; it contains announcements of quarterly meetings, news of the members, information on board actions, and membership lists. The STAA had also issued four Special Publications as of 1995; these included monographs on Timmeron Rockshelter (Hays County), field and laboratory methods in archeology, geomorphology of the Sabinal Canyon (Uvalde County), and the prehistory of the Olmos Basin (Bexar County).
Activities of the STAA revolve around the quarterly meetings, at which several papers are presented by members and invited guests. Governance is by a board of directors, composed of the elected officers (with the recent addition of the immediate past chairman), the editor of the journal, the newsletter editor, and the editor of Special Publications. Appointed officers include area consultants, field directors, and committee chairs (for standing committees). The organization annually presents the Robert F. Heizer Award for outstanding contributions to the archeology of South Texas by an STAA member. Other service-oriented awards include the Dee Ann Story Conservation Award, for individuals, families, or groups who aid historic preservation, and the Archeological Public Service Award, given to schools, city agencies, or firms whose activities have furthered the goals of archeology. Fieldwork has been an important STAA activity. Its first excavations were done in 1973–74 at the Granberg II site (41BX271) in San Antonio, followed by work at the St. Mary's Hall site (41BX229) in 1974–76. Since the late 1970s long-term excavations have been carried out at the Dan Baker site (41CM104). Surveys of areas around San Antonio and elsewhere in southern and south central Texas have been conducted, resulting in the recording of many prehistoric and historic sites. In 1991 the STAA initiated an annual field school, held over a seven-day period each fall. These have included excavations and surveys at the Quinta Medina site (41ME53) in Medina County and in the area of southern Bexar County around the proposed Applewhite Reservoir. In October 1995 the field school was held at site 41BX831, at Applewhite, and exposed an occupation of Late Paleo-Indian Angostura culture dating around 6800 B.C. Each summer the STAA awards several field school scholarships to college students participating in work in southern Texas or nearby areas. Such scholarships have gone to students at UT San Antonio, UT Austin, Southwest Texas State University, Texas Tech University, and other institutions.