Patients with antineutrophil cytoplasmic antibody–associated systemic vasculitis (AASV) have recently benefited from treatment advances that prolong life. AASV refers to a range of rare disorders characterized by small blood vessel inflammation and the production of antibodies against specific components within the neutrophils (e.g., Wegener’s granulomatosis, microscopic polyangiitis, and Churg-Strauss syndrome) (1). The inflammatory process can adversely affect organs, including the skin, lungs, and kidneys. AASV is marked by periods of remission and relapse, making its course highly uncertain. When critical organs are compromised, patients experience severe symptoms, including death. Treatment with corticosteroids and immunosuppressive drugs has proven beneficial, and has increased the likelihood of patient survival and sustained remission. Patients with AASV and their family members are now concerned with enhancing quality of life in addition to prolonging quantity of life (2). One central issue is chronic illness management (CIM), or efforts that patients and family members undertake to control AASV and minimize its negative impact on health status and functioning. AASV and its consequences are managed through activities, which may include strict adherence to medication regimens, visits to health professionals, nutrition changes, mild exercise, fatigue management, symptom monitoring, emotion management, and in some cases dialysis. Understanding the determinants of patients’ CIM is important because these behaviors affect illness progression (3,4) and could inform interventions. Here we focus on the interpersonal context of the lives of patients with AASV. There is considerable evidence demonstrating that support provided by persons who are close to these patients is associated with improved health behavior (5) and psychosocial functioning (6); however, interventions designed to increase support have been disappointing (7). Emerging literature on dyadic coping in the context of chronic illness (8) and rheumatic disease (9–11) integrates concepts from the field of relationship science into health-related research on social support. This literature offers a potentially useful process-oriented approach for examining support in couples facing chronic illness. The purpose of our article is to introduce a conceptual model of dyadic CIM that draws on recent theoretical and empirical work in relationship science and dyadic coping. This article is not meant to be a comprehensive review of social support and dyadic coping in rheumatic illness, but aims to introduce concepts from this emerging area and apply them to CIM in the context of AASV. We therefore do not report data, but instead use examples from our previous studies, and a current longitudinal study of CIM in couples coping with AASV, to illustrate the importance of the couple relationship to CIM. Three factors motivate our choice for focusing on marital partners in the context of CIM. First, prevailing CIM perspectives acknowledge that the interpersonal context may affect patient self-management efforts and, thus, patient outcomes (12). Second, research across diverse populations shows that marriage is strongly related to many beneficial health outcomes (13,14) and that spouses influence health-related perceptions and behaviors of partners (15– 17). These associations are well documented in couples coping with rheumatic diseases (9,17–21). Studies show that spouses can be effectively engaged in rheumatic illness coping interventions (10,22,23). Third, couples likely find AASV challenging to manage because of unpredictable periods of flares and remissions, treatment with medications that may have serious side effects, and the need for strict adherence to a variety of health behaviors (24). Supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (grant P60-AR-49465-03), the National Cancer Institute (grant R21-CA-108744), and Wegener’s Granulomatosis Association. Megan A. Lewis, PhD, Carolyn T. Kalinowski, MPH, Tracy M. Barrett, PhD, Robert F. DeVellis, PhD: Thurston Arthritis Research Center, University of North Carolina at Chapel Hill; Katherine R. Sterba, PhD: School of Public Health, University of Texas at Houston. Address correspondence to Megan A. Lewis, PhD, Department of Health Behavior and Health Education, Campus Box 7440, University of North Carolina, Chapel Hill, NC 275997440. E-mail: megan.lewis@unc.edu. Submitted for publication August 25, 2005; accepted in revised form January 19, 2006. Arthritis & Rheumatism (Arthritis Care & Research) Vol. 55, No. 4, August 15, 2006, pp 670–675 DOI 10.1002/art.22092 © 2006, American College of Rheumatology