We explored different routes to efficient outcomes in two-party negotiations that were conducted via electronic mail. Some participants negotiated with a member of an outgroup (a student at a competitor university) and some negotiated with a member of an ingroup (a student at the same university). In addition, some negotiators had personalized relationships with their opponents while others did not. When neither common ingroup status nor personalized relationship existed, negotiating dyads had significantly higher rates of impasse. These results are attributable to the positive influence of personalized relationships and common group membership on negotiation processes and rapport between negotiators.