While securing an optimal agreement is a pivotal milestone, this alone does not guarantee negotiators will obtain optimal outcomes. This study examines how integrative strategies, which reduce bias during bargaining (i.e., fixed-pie bias), can paradoxically increase bias during implementation (i.e., escalation of commitment bias) ultimately resulting in suboptimal outcomes. I present evidence that integrative strategies can increase self-justification for sunk costs involving relational capital and lead to goal substitution, where negotiators prioritize preserving the relationship over optimizing outcomes. This leads to both episode-specific and multi-episodic escalation of commitment. This research also explores how this effect is conditional on the distribution of responsibility for the failure, showing that when blame is shared equally, escalation intensifies. To test these ideas, I developed a high-fidelity negotiation simulation with experts in the film industry, collecting data over three weeks on 238 negotiators. Together, this study has important implications for future multi-stage and multi-episodic negotiation research.
