This paper investigates the contribution of involving patients for ideation of service innovation in the healthcare context by addressing the following two main research questions: (Q1) What can patients contribute with when invited to contribute with new ideas for improving primary care? and (Q2) How should patient involvement be managed – should they be involved with, or without, healthcare employee involvement? The research questions were addressed by a one-year longitudinal study of ‘innovation groups’ aimed at creating ideas to improve primary care centers. A longitudinal quasi-experimental approach was deployed consisting of three different settings with varying composition of the innovation group: 1) only healthcare employees, 2) only patients, 3) a mix of healthcare employees and patients. In total 180 ideas for service innovation were reported and assessed by four experienced experts using a web-based questionnaire including 8 assessment dimensions and a free text space, inviting the experts to comment on the idea. In addition, individual interviews were conducted which served the purpose of exploring healthcare employees’ value creation when generating ideas together with patients. The study shows that patient involvement during service innovation ideation brings a patient perspective to healthcare. The findings reveal that patient–healthcare employee interactions positively contribute to healthcare employees’ use knowledge as they started to refocus their ideas more towards the patient perspective. Further the study contributes by showing that patient involvement needs to be a focused and dedicated activity towards innovation as, for example, an innovation group, to bring a patient perspective during idea creation.