A successful transition from preschool to school demands continuity in education between the institutions: continuity in pedagogy, values and institutional structures. One way to achieve continuity is to learn how to do "boundary work" in the borderline of two activity systems. This article examines what kinds of discourses frame the problem-solving process in the context of inter-professional collaboration. The data consists of video-recorded, inter-professional discussions in the 2012-2013 (a total of 22.5 h). The project, called Flexible Preschool and School, aims to develop a new model for a smooth transition to school. In the project, professionals from preschool and school create joint activities and co-teaching, which is assumed to bridge the gap between pedagogies and assure the continuity of learning. The professionals' cultural thoughts in different kinds of problem-solving situations become visible in the discourses produced in the talk. These discourses describe their capacity for solving shared problems. Creating new innovations demands an understanding that complex problems require diverse knowledge. Considering the shared knowledge as valuable enough to put into practice is the way to create new forms of problem-solving. This is implemented by taking on the responsibility to be an active actor.