Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage. Pain is a dynamic process in which pain stimulus is modulated at all levels from the peripheral to the central nervous system. Regarding the duration, pain can be classified as acute and chronic. Acute pain occurs as a response to trauma, inflammation and surgical procedure. Acute pain is a central component of the body's stress response to injury. Because of this, approach to treating pain should be appropriate and aggressive in order to reduce the effects of pain on the organism, to optimize patient recovery and to reduce complications. An important precondition for effective analgesia is an objective assessment of pain intensity and assessment of all other factors related to the painful experience. For the evaluation of pain in clinical practice one-dimensional and multi-dimensional scales are commonly used. Treatment of pain can be divided into two major categories: pharmacological and nonpharmacological treatment. Pharmacological treatment includes systemic analgesia and administration of drugs via the methods of regional anesthesia. Balanced (multimodal) analgesia indicates use of two or more analgesics that, acting by different mechanisms, provide a stronger analgesic effect without increasing the incidence of side effects compared by incidence of side effects caused by increasing the dose of one drug. Basic drugs for regional analgesic tehniques are local anesthetics and opioids. Adjuvant drugs, such as alpha-2 agonists, steroids, anticonvulsants and NMDA-antagonists, are often added to improve and prolong analgesia. Treatment of postoperative pain should be adjusted to the type of surgery and analgesia should not represent a greater risk to the patient than the surgical procedure itself. Postoperative analgesia must be continued, uninterrupted, to the analgesia during the surgery. Infiltration anesthesia, peripheral nerve blocks, epidural and spinal block are the most commonly used techniques of regional anesthesia for treatment of postoperative pain. Analgesia is maintained by continuous infusion, by intermittently added drug or as patient-controlled analgesia (PCA). PCA allows for greater individualization of therapy and improves patient satisfaction. Compared with systemic opioid analgesia, regional analgesia tehniques provide excellent postoperative analgesia with reduced need for opioids.