In the context of the advancement of person-centered care models, the promotion of the participation of patients with chronic illness and complex care needs in the management of their care (self-management) is increasingly seen as a responsibility of primary care nurses. It is emphasized that nurses should consider the psychosocial dimensions of chronic illness and the client’s lifeworld. Little is known about how nurses shape this task in practice. The aim of this analysis is to examine how primary care nurses understand and shape the participation of patients with chronic illness and complex care needs regarding the promotion of self-management. Guided interviews were conducted with nurses practicing in primary care and key informants in Germany, Spain, and Brazil with a subsequent cross-case evaluation.