Background: Patients newly diagnosed with inflammatory arthritis (IA) request regular consultations and support from health professionals to manage physiological, emotional, and social challenges. Evidence suggests that providing a tailored multi-component self-management program may benefit disease management. However, there is a lack of evidence of effective interventions with multiple components targeting the needs of this group. Therefore, the aim of this study was to develop a self-management intervention targeting newly diagnosed patients with IA, following the Medical Research Council (MRC) framework for developing complex interventions. Methods: The development of the complex self-management intervention covered three steps. First, the evidence base was identified through literature reviews, in which we described a preliminary nurse-led intervention. Secondly, we chose Social Cognitive Theory as the underlying theory along with Acceptance and Commitment Theory to support our communication strategy. Thirdly, the preliminary intervention was discussed and further developed in workshops to ensure that the intervention was in accordance with patients’ needs and feasible in clinical practice. Results: The developed intervention comprises a 9-month nurse-led intervention (four individual and two group sessions). A physiotherapist and an occupational therapist will attend the group sessions along with the nurse. All sessions should target IA-specific self-management with a particular focus on medical, role, and emotional management. Conclusion: Through the workshops, we involved all levels of the organization to optimize the intervention, but also to create ownership and commitment, and to identify barriers and shortcomings of the preliminary intervention. As a result, from the existing evidence, we believe that we have identified effective mechanisms to increase self-management in people newly diagnosed with IA. Further, we believe that the involvement of various stakeholders has contributed significantly to developing a relevant and feasible intervention. The intervention is a nurse-led complex self-management intervention embedded in a multidisciplinary team (named NISMA). The intervention is currently being tested in a feasibility study.