Modernization policies in primary care, such as the introduction of out-of-hours general practice cooperatives, signify a marked departure from many service users’ traditional experiences of continuity of care. We report on a case study of accounts of service users with chronic conditions and their caregivers of continuity of care in an out-of-hours general practice cooperative in Ireland. Using Strauss and colleagues’ Chronic Illness Trajectory Framework, we explored users’ and caregivers’ experiences of continuity in this context. Whereas those dealing with “routine trajectories” were largely satisfied with their experiences, those dealing with “problematic trajectories” (characterized by the presence of, for example, multimorbidity and complex care regimes) had considerable concerns about continuity of experiences in this service. Results highlight that modernization policies that have given rise to out-of-hours cooperatives have had a differential impact on service users with chronic conditions and their caregivers, with serious consequences for those who have “problematic” trajectories.