Shock is a multifactorial syndrome that requires a systematized approach for its identification, classification and adequate treatment. Despite advances in medicine, different studies and clinical series indicate that mortality can reach up to 50%. The only variable that has been shown to be consistent in reducing mortality, regardless of the cause of shock, is its early recognition and management. This manuscript aims to provide a theoretical framework about the presentation of the patient in shock in the emergency department, describe its main characteristics and guide the study and time-dependent treatments from its first evaluation by the medical team. It begins with the presentation of clinical cases relevant to the topic. Then it reviews the pathophysiology of the shock phenomenon and its subtypes. Finally, it offers tools for evaluation and treatment in the Emergency Service.