Previous research has examined the various types of online infidelity, gender differences in online sexual behaviors, and relationship consequences of online affairs. Despite this attention, there remains a research gap regarding ways to prevent online infidelity. When couples seek therapy to address this issue, therapists report a lack of specific preparedness. This qualitative research project focused on methods for assisting couples by studying how they develop an agreement regarding appropriate and inappropriate online behaviors. Grounded theory was used to analyze the data from dyadic interviews with 12 engaged heterosexual couples. The interviews generated five common steps in the process of developing an agreement: (a) discuss the various online activities the couple participates in online; (b) define online infidelity; (c) discuss which activities are appropriate and which are not appropriate; (d) develop rules; and (e) state what occurs when an agreement is violated. Three couples had developed an agreement prior to the study and two couples developed an agreement through the process of the interview. Seven couples reported, however, that an agreement would not be beneficial in their relationship. These couples suggested using alternatives to an online behavior agreement including have mutual respect, eliminate questionable activities, get to know their fiancé or fiancée, and not participate in any online activities that they would not do in front of their partner. Although the study presupposed that couples would embrace the development of a mutual agreement, most couples elected to use other approaches. The results raise useful questions about couple readiness for structured prevention strategies and therapist approaches for clinical intervention.