Patient registries provide valuable contributions to the field of rheumatology for both quality control and scientific purposes. With respect to the latter, patient registries are among the most important datasets used for longitudinal observational studies in rheumatic diseases, which are in turn an essential complement to data obtained from randomized, controlled trials. In Sweden a number of registries are available for such studies, ranging from general medical registries such as the in-patient registry, to rheumatoid arthritis (RA)-specific inception cohorts and biologics registries focusing on a specific patient population defined by a group of treatments. In recent years it has become particularly clear that questions regarding new therapies, their use in practice and their long-term safety, as well as aspects such as pharmacoeconomics, cannot fully be assessed using the data from clinical trials, and that registries are indispensible to obtain accurate answers to such questions. In this review we describe the Swedish rheumatology registries, including the Swedish RA registry and the Swedish biologics registries ARTIS (Antirheumatic Therapies Iin Sweden), SSATG (Southern Sweden Antirheumatic Therapy Group), and STURE (Stockholm Tumor Necrosis Factor-a Follow-up Registry). Data obtained from analyses based on these registries are reviewed. It is concluded that rheumatology registries are excellent tools for improving our knowledge base regarding rheumatic diseases.