The fascial system is a complex connective tissue network that provides structural integrity, mobility, and sensory innervation of the body. Despite the high prevalence of fascial disorders (chronic back pain, myofascial pain syndrome, and fibromyalgia), their pathogenesis remains insufficiently understood, and current therapeutic strategies are not always effective. Therefore, a need exists to synthesize contemporary data on the anatomy, histology, pathophysiology, and theoretical models of the fascial system, while critically evaluating treatment methods for fascial pathology. This review presents information on the anatomical and histological structure, as well as the functional heterogeneity, of fascia. Three theoretical models are analyzed: biotensegrity, mechanotransduction, and myofascial chains. The study examines key pathophysiological mechanisms, including myofibroblast activation, ischemia, acidosis, hyaluronan depolymerization, and peripheral and central sensitization. It also systematizes various treatment methods such as manual therapy, physical exercise, dry needling, acupuncture, shockwave therapy, and pharmacotherapy (including nonsteroidal anti-inflammatory drugs, glucocorticosteroids, local anesthetics, and muscle relaxants), alongside rehabilitation approaches. The findings may be of value for rheumatologists, orthopedists, neurologists, and physical rehabilitation specialists.