The objective of this study is to determine the use and efficacy of spa therapy in patients with a wide spectrum of rheumatic and musculoskeletal diseases under real-life clinical practice circumstances. In this retrospective observational study at the Medical Ecology and Hydroclimatology Department of Istanbul Faculty of Medicine, the records of all adult patients with rheumatic and musculoskeletal diseases who were prescribed a spa therapy in various health resorts in Turkey between 2002 and 2012 were analyzed. Patients sojourned to and stayed at a health resort and followed a usual 2-week course of spa therapy. The patients were examined within a week before and after the spa therapy at the department by the physicians and outcome measures were pain intensity (visual analog scale, VAS), patient's general evaluation (VAS), physician's general evaluation (VAS), Health Assessment Questionnaire (HAQ), Lequesne's Functional Index (LFI), Western Ontario and McMaster Universities Index (WOMAC), Waddell Index (WI), Neck Pain and Disability Scale (NPDS), Shoulder Disability Questionnaire (SDQ), Fibromyalgia Impact Questionnaire (FIQ), and Beck's Depression Inventory (BDI). In total, 819 patients were included in the analysis. The diagnoses were 536 osteoarthritis; 115 fibromyalgia; 50 lumbar disc herniation; 34 cervical disc herniation; 23 nonspecific low back pain; 22 ankylosing spondylitis; 16 rheumatoid arthritis; 9 rotator cuff tendinitis; and 14 other conditions/diseases including scoliosis, stenosing flexor tenosynovitis, congenital hip dislocation in adult, Behçet's disease, de Quervain tendinopathy, psoriatic arthritis, osteoporosis, fracture rehabilitation, and diffuse idiopathic skeletal hyperostosis. Statistically significant decrease in pain scores was found in all patients except hip osteoarthritis (p = 0.063) and rheumatoid arthritis (p = 0.134) subgroups; and statistically significant improvement in function in all patients except hip osteoarthritis (p = 0.068), rheumatoid arthritis (p = 0.111), and rotator cuff tendinitis (p = 0.078) subgroups. In daily clinical practice, spa therapy is prescribed and practiced mainly for osteoarthritis, then fibromyalgia, lumbar/cervical disc herniation, and nonspecific low back pain; and less for ankylosing spondylitis, rheumatoid arthritis, and rotator cuff tendinitis. The study results suggest that real-life spa therapy may be effective in a variety of rheumatic and musculoskeletal diseases by improving pain and function.