The number of HIV-AIDS cases among African American women (AAW) continues to rise. AAW currently account for about 65% of AIDS diagnoses among women in the United States. Furthermore, among AAW living with HIV-AIDS, heterosexual transmission remains the leading cause of HIV spread. Indeed, examining AAWs sex partner selection patterns will be a key step in understanding how to support HIV prevention for this population. A grounded-theory study was conducted to examine what factors influence AAW's alternation between monogamous and nonmonogamous sexual relationships. To explore this phenomenon, we recruited 14 urban AAW between the ages of 18 and 30 for interviews. The findings revealed that AAW's sex partner selection patterns in consensual sexual relationships were influenced by the "getting-to-know" process, the male's relationship preference, a woman's risk perception, and how the role of sex is defined. The results of this study can provide insights for future interventions seeking to curb HIV rates among AAW from urban communities. © The Author(s) 2012.