This chapter discusses the diagnosis, evaluation and management of shock. It presents special circumstances which make diagnosis and management of shock difficult in pediatric and pregnant patients. Shock should be suspected when patients present with a constellation of signs including ill-appearance, tachycardia, tachypnea, hypotension, and oliguria. The principles of shock management include specific therapy for treating the underlying cause, and general therapy to manage the shock syndrome. Recognition of shock is difficult due to variations in age-dependent vital signs, difficulty in assessing mental status, and the non-specificity of early manifestations of shock such as irritability and poor feeding. Elderly patients experience significantly more morbidity and mortality from all causes of shock due to their limited ability to augment cardiac output and maintain vascular tone. Elderly patients often have multiple comorbidities or use multiple medications that distort the diagnosis and management of shock.