New product introduction refers to all activities that are required to make a product possible to produce in planned volumes. To ensure smooth new product introduction, product and production developers work in a cross-functional and integrated way. Because of high degree of novelty during new product introduction and interdependencies between those involved knowledge boundaries are created. As prior research argues, different types of knowledge boundaries require different integration processes. For example, integration at a syntactic boundary is established by transfer of domain-specific knowledge across a boundary, while coping with semantic boundary requires a process of translation where learning about the differences and dependencies at the boundary is required. To be able to understand how to integrate product and production development across knowledge boundaries and hence support new product introduction it is important to understand what types of boundaries need to be crossed. To overcome the shortcomings of the prior research, this paper focuses on knowledge boundaries and prerequisites for successful integration in new product introduction. It is based on success stories from three large Swedish companies. This paper addresses transdisciplinary challenges and contributes to literature on boundary crossing during new product introduction and to practice.