Supply chain collaboration is usually adopted by manufacturers as a strategic measure to increase overall supply chain performance. However, such collaborations arguably have the highest failure record of the various supply chain management practices that are currently being applied. Part of the problem has been the uncertain external environment, an overreliance on technology, and lack of trust among partners. Based on Transaction Cost Economics (TCE) and Relational Exchange Theory (RET), it is clear that environment, asset specificity, and trust are key determinants for the success of collaborations among firms. However, the fuzziness of the interdependency among these determinants and their influences on supply chain collaborative processes still remains unknown. This study thus focuses on Taiwanese manufacturing firms as an example case, and empirically probes the relationships among these dimensions and their effects on these processes. To accommodate the vagueness of human opinions, the fuzzy Decision Making Trial and Evaluation Laboratory (DEMATEL) technique is applied to examine this issue, and to produce a causal relations map. This study also provides a discussion and insights for supply chain practitioners.