Informed by social constructionism, for example the work of Stenner (1993), Lawes (1999) and feminist poststructural writing, for example Willott & Griffin (1997), the study examined discursive constructions of ‘infidelity’ and ‘monogamy’ as contextualized by accounts of personal relationships. Using an integrated form of discourse and conversational analysis, ‘Man: A Sexual Being’, ‘Passive/Aggressive Infidelity’ and ‘Relationship Parameters’ discourses were examined. In addition the ‘Monogamy-A State of Mind’ and ‘Infidelity-In the Eye of the Beholder’ repertoires were explored. It was concluded that a thorough exploration of these discourses and repertoires reflected the fluid and contextually dependent constitution of ‘infidelity’ and ‘monogamy’ in personal relationships. Such critical analysis joins a body of research that may be seen as providing a lever for challenging dominant meaning systems that enable the construction of particular personal and sexual relationships as ‘normal’, ‘right’ or ‘appropriate’.