Family Medicine Groups (FMGs) are the most recently developed primary care organizations in Quebec (Canada). Nurses within FMGs play a central role for patients with chronic diseases (CD). However, this complex role and the nursing activities related to this role vary across FMGs. Inadequate knowledge of nursing activities limits the implementation of exemplary nursing practices. This study aimed to describe FMG nursing activities with patients with CD and to describe the facilitators and barriers to these activities. A multiple‐case study was (...) performed with ten nurses practicing among patients with CD in FMGs. Five data sources were used to provide an in‐depth description of nursing activities and the facilitators and barriers to the development of these activities. After qualitative data analysis, findings show that nursing activities are clustered into five domains: Global assessment of the patient, Care management, Health promotion, Nurse–physician collaboration, and Planning services for patients with CD. Activities vary depending on contextual factors identified in each case. This multiple‐case study provides a clear description of nursing activities with patients with CD. There is a need for improved nursing activities and expertise in domains of activities that are less present in FMGs, such as case management and interprofessional collaboration. (shrink)