Issues related to corporate strategic alliances can be approached from three perspectives: (1) pre-contractual issues (alliance motivation and partner selection), (2) contractual issues (contract negotiation), and (3) post-contractual issues (alliance operation and management). This study focuses on the successful operation and management of alliances for enhancing synergistic effects and achieving joint objectives after the formation of strategic alliances, and proposes mutual reciprocity-based coordination efforts (value-sharing, congruence-centered, and rapport-building coordination efforts) as core strategies. Specifically, the study aims to structurally examine the relationships between mutual reciprocity strategies in strategic alliances, the relationship with partner firms (inducing partner cooperation, inter-firm mutual adaptation, and restraining partner opportunistic behavior), and effectiveness (transaction cost reduction and relationship continuity intention). Data were collected on 156 alliance contracts among domestic firms, and the empirical analysis results are as follows. First, firms' mutual reciprocity strategies enhanced partner cooperation and mutual adaptation with partners (H1 and H2), and cooperation and mutual adaptation were found to mutually influence each other (H3). Second, cooperative behavior restrained partner firms' opportunistic behavior, thereby reducing transaction costs (H4 and H7), and reduced transaction costs in turn increased relationship continuity (H10). Meanwhile, mutual adaptation was found to directly influence relationship continuity without being mediated by the restraint of opportunistic behavior and transaction cost reduction (H8). The conclusion of this study summarizes the results and discusses implications and limitations.