In the law of torts, malpractice, also known as professional negligence, is an "instance of negligence or incompetence on the part of a professional".

Professionals who may become the subject of malpractice actions include:

• medical professionals: a medical malpractice claim may be brought against a doctor or other healthcare provider who fails to exercise the degree of care and skill that a similarly situated professional of the same medical specialty would provide under the circumstances.
• lawyers: a legal malpractice claim may be brought against a lawyer who fails to render services with the level of skill, care and diligence that a reasonable lawyer would apply under similar circumstances.
• financial professionals: professionals such as accountants, financial planners and stockbrokers, may be subject to claims for professional negligence based upon their failure to meet professional standards when providing services to their clients.
• architects and engineers: a construction professional may be accused of professional negligence for failing to meet professional standards in the design and construction of buildings and structures.