Dutch general practitioners (GPs) and medical specialists (MSs) create collaborative patient care agreements (CPCAs) to improve intraprofessional collaboration. We set out to identify contradictions between the activity systems of primary and secondary care that could result in expansive learning and new ways of working collaboratively. We analysed nineteen semi-structured interviews using activity theory (AT) as a theoretical framework and using these two activity systems as the units of analysis. There were contradictions within and between the activity systems related, for example, to different understandings of ‘care’ in generalist and specialist settings. GPs and MSs were able to identify contradictions and learn expansively when they iteratively co-created CPCAs in groups. They found it much harder to tackle contradictions, however, when they disseminated these tools within their respective professional communities, leaving unresolved contradictions and missed opportunities for collaboration. This research shows the educational benefits of taking collective responsibility for improving collaborative patient care.