The most common serious complications of intramuscular injections in children are muscle contractures and nerve injury. Muscle contracture occurs most commonly after injections in the anterior and lateral thigh, and sciatic nerve injury is the most frequently reported serious complication of the gluteal area. The technique of administering intramuscular injections involves attention to the appropriate site of needle insertion, needle size, and angle of injection. Suggested techniques with illustrations are included. The appropriate site of injection depends upon the age and size of the child. Multiple injection sites may be preferable in some cases. Compliance with meticulous technique may reduce the incidence of complications; however, complications can occur in spite of every appropriate precaution.