Modularization is a well-known approach that can potentially mitigate many of the current construction industry's challenges including, for example, poor productivity, shortages in skilled labors, and poor safety performance. Recent studies have shown that contractual risks and disputes are still considered one of the top factors affecting the performance of modular processes. Many research efforts have analyzed disputes and their causes in the construction industry, but none of them addressed the unique and complex sources of disputes that could be associated with the use of modularization. The goal of this paper is to investigate dispute causation in modular construction projects. To this end, this study adopted an integrated multistep analytical research methodology. First, the authors collected and analyzed a total of 39 publicly available law cases of modular construction disputes in the US. Second, social network analysis was performed to identify the most common causes leading to disputes in modular construction projects. Third, spectral clustering was conducted to group the dispute causes based on the strength of their interconnectivities. Fourth, association rule analysis and Apriori algorithms were used to identify key associations of causes that would most likely trigger modular construction disputes. The results indicated that payment holds and delays, delay in project completion, poor communication among the project stakeholder, and lack of collaboration between various trades are common causes of disputes in modular construction projects. Also, as the authors were able to cluster the 40 identified causes of disputes into four clusters, the most significant associations of dispute causes were determined and quantified within each identified cluster. Further, the findings reflected that modular construction disputes are mostly triggered by the occurrence of multiple causes rather than by just a single cause. This paper adds to the body of knowledge by helping practitioners manage and control sources of disputes in modular construction projects. This should help to minimize dispute occurrence during modular processes, and thus maximize capitalization on modularization benefits. Ultimately, the outcomes of this paper should direct researchers and industry practitioners toward the contractual aspects of modularization that require appropriate adjustments and revision so as to better account for the uniqueness of modular processes within today's complex construction industry.