This meta-analysis evaluates transaction cost theory (TCT) in explaining organizational boundary decisions (make, buy, or ally). The study synthesizes empirical research on TCT, focusing on the relative importance of transaction dimensions (asset specificity, uncertainty, and transaction frequency) in shaping governance choices (hierarchical, relational, or market). The results support TCT's predictions for both make versus buy and ally versus buy decisions. However, the study finds that asset specificity does not have stronger predictive power than uncertainty. Hierarchical and relational governance appropriately aligned with transaction dimensions both led to enhanced performance. The study also addresses limitations in previous TCT research, including the lack of quantitative integration across disciplines and the difficulty in comparing the effects of different transaction dimensions. The analysis also questions the adequacy of TCT in explaining relational governance, which involves joint value maximization rather than just cost minimization. The study also highlights the normative implications of TCT, noting that empirical findings have been inconsistent regarding the effect of governance choice on performance. The meta-analysis provides insights into the relationship between governance choice and performance by explicitly incorporating the selection decision. The study tests several hypotheses regarding the effects of transaction dimensions on governance choice and performance. The results support the idea that hierarchical governance is preferred when asset specificity and volume uncertainty increase, while market governance is preferred when technological uncertainty increases. Relational governance is preferred when asset specificity increases, but market governance is preferred when uncertainty increases. The study also finds that asset specificity has a greater effect than uncertainty on governance choices. The study concludes that TCT remains a dominant theoretical framework for explaining organizational boundary decisions, but further research is needed to fully understand the role of transaction dimensions in shaping governance choices and performance.This meta-analysis evaluates transaction cost theory (TCT) in explaining organizational boundary decisions (make, buy, or ally). The study synthesizes empirical research on TCT, focusing on the relative importance of transaction dimensions (asset specificity, uncertainty, and transaction frequency) in shaping governance choices (hierarchical, relational, or market). The results support TCT's predictions for both make versus buy and ally versus buy decisions. However, the study finds that asset specificity does not have stronger predictive power than uncertainty. Hierarchical and relational governance appropriately aligned with transaction dimensions both led to enhanced performance. The study also addresses limitations in previous TCT research, including the lack of quantitative integration across disciplines and the difficulty in comparing the effects of different transaction dimensions. The analysis also questions the adequacy of TCT in explaining relational governance, which involves joint value maximization rather than just cost minimization. The study also highlights the normative implications of TCT, noting that empirical findings have been inconsistent regarding the effect of governance choice on performance. The meta-analysis provides insights into the relationship between governance choice and performance by explicitly incorporating the selection decision. The study tests several hypotheses regarding the effects of transaction dimensions on governance choice and performance. The results support the idea that hierarchical governance is preferred when asset specificity and volume uncertainty increase, while market governance is preferred when technological uncertainty increases. Relational governance is preferred when asset specificity increases, but market governance is preferred when uncertainty increases. The study also finds that asset specificity has a greater effect than uncertainty on governance choices. The study concludes that TCT remains a dominant theoretical framework for explaining organizational boundary decisions, but further research is needed to fully understand the role of transaction dimensions in shaping governance choices and performance.