School teams are becoming more and more interprofessional, especially in the context of inclusive education. However, to collaborate in an interprofessional manner is still a challenge for everyone involved and there are few studies that describe the current scope and ways of cooperation found in primary schools and their relation to beneficial school support. In a cross-sectional study, interprofessional staff members (N = 251) in German inclusive primary schools (N = 38) self-assessed the current and desired level as well as various modes of interprofessional collaboration in their daily work. They also assessed the motivational support from the principal and the institutional school support for teamwork. Main results show that interprofessional collaboration is already rated as high and wished as even more intensive in the sample, whereas various modes of cooperation are used to different extents. The desired level of collaboration is significantly higher in pedagogical staff than in primary school teachers. Overall school support for teamwork is perceived as moderate and shows positive correlations to all reports on staff collaboration. The role of school support as a booster for teamwork in interprofessional school staff and a way to improve their qualification to act interprofessionally is discussed.