Collaboration is an essential element of new product development (NPD). This research examines the associations between four types of information technology (IT) tools and NPD collaboration. The relationships between NPD practices and NPD collaboration are also examined. Drawing on organizational information processing theory, we propose that the relationships between IT tools and NPD collaboration will be moderated differently by three project complexity dimensions, namely, product size, project novelty, and task interdependence, due to the differing nature of information processing necessitated by each project complexity dimension. Likewise, the moderation effects of the project complexity dimensions on the relationship between NPD practices and NPD collaboration will also be different. We test our hypotheses using data from a sample of NPD projects in three manufacturing industries. We find that IT tools are associated with collaboration to a greater extent when product size is relatively large. In contrast, IT tools exhibit a smaller association with collaboration when project novelty or task interdependence is relatively high. NPD practices are found to be more significantly associated with NPD collaboration under the contingency of high project novelty or high task interdependence. The findings provide insights about circumstances where several popular IT tools are more likely to facilitate collaboration, thus informing an NPD team's IT adoption and use decisions.