The range of the brown widow spider Latrodectus geometricus C. L. Koch includes much of Africa and South and Central America. This medically important spider has been recently introduced to Japan, Indonesia, Papua New Guinea, Australia, Hawaii, and California. After the identification of the brown widow spider in New Orleans, LA, and southern Mississippi, surveys in the southeastern United States were conducted from the fall of 2006 through February 2008. We found populations of brown widow spiders in Georgia, Texas, and multiple localities in southeastern Louisiana and Mississippi. In Mississippi, specimens were collected as far north as a county bordering Tennessee. In New Orleans, the brown widow spider has been commonly collected from various locations where human contact is likely.