A living will, also called a treatment directive, is a type of advance directive that documents personal wishes about end-of-life medical treatment in case decision-making or communication abilities are lost. A living will specifies the conditions under which certain kinds of treatment or life-support measures would or would not be wanted.

A living will can be changed or revoked at any time and will not take effect until a person is no longer able to make or communicate decisions. Copies of living wills should be given to and discussed with a person's health professional and family members.

Although living wills can be written without the help of an attorney, legal advice may be useful. This is especially true for people who live in states where living wills are not recognized or the laws governing them are unclear. Many hospitals and nursing homes provide living will forms that comply with state-specific requirements.