Systemic lupus erythematosus (SLE) is a chronic disease which can affect any organ, and the impact of the condition will affect each person differently. There are few qualitative studies including the experiences of both women and men with a diagnosis of SLE corresponding to the American College of Rheumatology (ACR) criteria where both negative and positive impacts of the disease have been presented. The aim was to describe how patients with established SLE experience their illness in everyday life, including both negative and positive aspects. Four focus group interviews were conducted with 16 women and three men with SLE according to ACR criteria, with varied disease activity and no or little organ damage. The interviews were tape recorded, transcribed verbatim and analysed using qualitative content analysis. Two themes emerged: multifaceted uncertainty contained the categories 'an unreliable body', 'obtrusive pain and incomprehensible fatigue', 'mood changes and worries', 'reliance on medication and health care'; Focus on health and opportunities included 'learning process implying personal strength', 'limitations and possibilities in activities and work', 'a challenge to explain and receive support' and 'living an ordinary life incorporating meaningful occupations'. While we expected to find a mainly negative impact, positive aspects were also described. Our findings were complex and showed that patients with established SLE can experience both uncertainty and opportunities. This highlights the importance for healthcare professionals of gaining a better understanding of patients' uncertainty, to enable them to support patients, allowing them to focus on health and opportunities. Measurement instruments that capture different aspects of uncertainty and opportunities needs to be developed.