This study extends past research on the impact of alternatives in dyadic negotiation by (a) providing negotiators with the mere possibility to negotiate with an outside party and (b) examining the moderating role of the negotiators' social motive. Business students engaged in face-to-face negotiations, which were audio-taped and transcribed. None, one, or both dyad members were provided with an exit option- the possibility to leave the current negotiation and start new negotiations with someone else. Dyads were also given instructions to maximise own outcomes (egoistic motive) or to consider both own and the other's outcomes (prosocial motive). Results showed that, as expected, dyads with a one-sided exit option engaged in more distributive and less integrative behaviour, adn obtained lower joint outcomes than dyads having either two-sided or no exit options. However, this effect occurred only under an egoistic rather than a prosocial motive. No differences were found for negotiations with two-sided exit options compared to negotiations without exit options, suggesting one's own exit option counter-balanced by the other's escape possibility. Our results indicate that negotiators who wish to maximize personal as well as joint outcomes should try to combine a power advantage in terms of exit options with a shared prosocial orientation. Copyright (C) John Wiley & Sons, Ltd.