Abstract: This work grapples with the ordinariness of infidelity – one of the ultimate transgressions in intimate relationships and its relationship to polygyny and divorce in Peponi, a rural Swahili Muslim fishing village in coastal Tanzania. Women in Peponi, push back against naturalizing arguments for polygyny, and unambiguously prefer infidelity to polygyny. In fact, they openly discuss their preference for husbands to have girlfriends and lovers rather than second and third wives. Most women articulate a desire for monogamous, romantic, and companionate marriage, and simultaneously anticipate their husbands will “look outside the marriage.” They argue infidelity is not their greatest provocation. Infidelity, and women’s tolerance of the it, must be understood in the context of men’s pursuit of polygyny and the impact it can have on their marriage (Keefe 2015, 2016). Women in Peponi openly discuss their preference for their husband’s infidelity in the form of girl friends, secret and informal wives, and short term affairs to their pursuit and achievement of a second or third wife. In fact, polygyny, it’s threat and reality, regularly prompt a path to divorce for most women. It is in this context that women prefer and, in their own way, choose infidelity.