Medical malpractice is a legal cause of action that occurs when a medical professional deviates from standards in his or her profession, thereby causing injury to a patient.

Medical malpractice is professional negligence by act or omission by a health care provider in which the treatment provided falls below the accepted standard of practice in the medical community and causes injury or death to the patient, with most cases involving medical error. Standards and regulations for medical malpractice vary by country and jurisdiction within countries. Medical professionals may obtain professional liability insurances to offset the risk and costs of lawsuits based on medical malpractice.