Fibromyalgia (FM) can be conceptualized as a failed attempt of our main complex adaptive system (the autonomic nervous system) to adjust to a hostile environment. FM cannot be fully understood through the prevailing linear-reductionist medical model. Conversely, FM can be explained using the new complexity theory paradigms. Relentless sympathetic hyperactivity in FM may be a sign of allostasis. Similarly sympathetic hyporeactivity to stress may indicate allostatic load. Dorsal root ganglia have been suggested as important sympathetic-nociceptive short-circuit sites. Autonomic dysfunction also explains non–pain-related FM features. Preliminary genetic evidence supports FM’s dysautonomic nature. A scientific holistic therapy is proposed to harmonize rigid complex systems and, in doing so, to help to improve FM symptoms.