[영문]Migrants form nonfamilial ties in urban destinations, which could compete with origin families for a share of remittances. A framework of competing commitment predicts that new relationships affect remittances depending on the extent to which they substitute for the benefits provided by origin families. Analyses of data from urban migrants in Kenya show that serious nonmarital sexual partners substitute for psychosocial support from the rural family and that material transfers migrants give to these partners significantly reduce remittances. The findings have implications for the ways scholars conceive of competition, the nature of exchange, and substitution of support across intimate relationships.