Despite growing evidence of a positive impact of Information Technology (IT) investments on firm performance, the variations in the results across organisations are still significant. This research takes a fresh approach by addressing complementarity impacts of organisational practices on three different dimensions of IT business value (ITBV). The goal is to identify important organisational practices and empirically test the synergistic relationships among them and their impacts on different dimensions of IT business value. We implemented an integrative approach to analyse the complex interactions among multiple organisational practices. First, we categorised ITBV into four dimensions based on different management objectives: strategic, informational, transactional and organisational transformation. Second, organisational configuration for each ITBV dimension is identified using regression trees. Third, a formal complementarity test was performed on each configuration pattern. Our findings indicate that the set of organisational practices affecting each dimension of ITBV is different. Hence, IT complementary factors that affect particular dimensions of ITBV do not necessarily have the same effect on other dimensions.