I propose a grounded process model of product innovation projects that are initiated by industrial firms and implemented jointly with not-for-profit technology institutions such as technological universities and government research laboratories. The proposed model is limited to those joint product development projects between collaborators with complementary expertise, that are of strategic importance to both collaborators and involve the joint creation of new technology or significant improvement over present technology. The model contributes significantly to the literature on collaborative product development by depicting in detail the essential linkage of antecedent conditions and motivations for the joint project initiation, to the actual project implementation process in which the two collaborators contribute complementary resources, and further to the project's expected consequences. The process model has been developed by synthesizing in-depth case studies of such university-industry joint product innovation projects, and aids understanding of effective processes for their initiation and implementation.