Post-stroke upper extremity (UE) impairment usually implies initial weakness, with subsequent diminished dexterity and limitation or incapacity for reaching, transport and grasping movements since the onset. Survivors may regain partial or, less often, complete muscle strength in the affected UE during the recovery process. However, a persistent degree of weakness and evolution to secondary complications as spasticity (characterized by increased flexor hypertonia), shoulder pain and contractures is frequent. These additional issues are associated with greater impairment, worse function and lower health-related quality of life. Treatment interventions for hemiparesis after stroke usually include stretching, strengthening of antagonist muscles, splinting, oral medications, and focal injections (phenol or botulinum toxin) and intrathecal baclofen. However, the amount, intensity and length of therapies still need further investigation. Despite adequate traditional treatment, a high number of patients are still permanently limited as a consequence of stroke. Based on motor learning theories, recent studies have demonstrated that intensive, repetitive, task-oriented therapies can help the paretic extremity "relearn" how to perform movements that were lost after brain damage.