Laser therapy and capacitive-resistive diathermy (CRD) are currently among the instrumental therapies most used in physiotherapy, due to their effectiveness as well as to their practicality and flexibility of use. Laser therapy uses laser light to obtain therapeutic - prevalently analgesic, anti-inflammatory and biostimulant - effects. The biological effects depend on the type of source and the interaction with the chromophores present in the tissues. Therapeutic lasers can be classified into different types based on the source (He-Ne, Diodes, CO2 and Nd-YAG, the most used) and the intensity of supply (LLLT and HLLT). CRD is a form of endogenous thermotherapy (radio wave diathermy) that uses frequencies between 0.45 and 1.2 MHz. It generally has two delivery modes with different biological targets: resistive and capacitive. The biological effects are predominantly biostimulant and hyperthermic. Both therapies are used in the treatment of numerous musculoskeletal system disorders, singly or in combination. The appropriateness of laser treatment and CRD depends on the type of tissue involved, the underlying pathology and the clinical phase of the disease. It is essential to know the characteristics of each therapy as well as the type of patient, which can also condition the appropriateness of an indication.