Effects of nine variables on compromising behavior and time to resolution were evaluated by a meta-analysis of published bargaining experiments reported over a 25-year period. The strongest effect sizes were obtained for the variables of negotiator's orientation, prenegotiation experience, time pressure, and the initial distance between positions. The orientation effect was particularly strong when it was communicated to bargainers by constituents or by the experimenter; the position distance effect was stronger for cognitive than for interest conflicts. Significantly weaker effect sizes were shown for opponent's concession strategy, representation, and accountability. The weakest effects occurred for the large versus small issues and visibility variables. These results challenge the assertion that group representation is a key determinant of competitive behavior in bargaining. Strong pressures on representatives to be accountable to their constituents did not increase the size of the effects. Analyses of differences in procedures used in the strongest and weakest effect size studies in each category suggest a number of conditions under which bargainers are likely to be intransigent.