Hydrotherapy is aimed at evoking short-term and long-term adaptation-mechanisms of patients. This meansthat a patient should be able to adapt to the changed environment, both mentally and physically. Hydrotherapy is widely used to treat patients with generalised rheumatic diseases. Hydrotherapy may be applied as a single therapy, in combination with other therapeutic interventions or as one part of a complex series of stimuli as e.g. during spa therapy. A treatment regimen in water is constructed according to the same rules as dry land exercise. However, methods specifically designed or adjusted for hydrotherapy can be used. The Halliwick is suitale in particular to facilitate arthrokinetic reactions as a part of training postural stability. The Bad Ragaz Ring is a hydortherapy modification of proprioceptive neuromuscular facilitation. Patterns of arms, legs and trunk are used to increase muscle function and flexibility. Other techniques are applicable in water too: mobilization and manipulation techniques of the joints can be integrated in hydrotherapeutic methods. The continuous research is needed for many interesting issues of hydrotherapy in new future.