Advance directives are designed to establish a person's preferences for treatment if the person becomes incompetent in the future or unable to communicate those preferences to treatment providers. Mental health advance directives are similar to the more commonly used directives for end-of-life medical decisions. A patient must be competent to execute a mental health advance directive, and the directive must clearly express the patient's wishes. Once directives are executed, steps must be taken to ensure compliance, including adequate dissemination to providers, and to ensure that proxy decisions are consistent with the patient's treatment preferences. Potential effects of mental health advance directives include enhanced consumer empowerment; improved functioning; improved communication between consumers, family members, and providers; increased tolerance for consumer autonomy at the organizational level in community mental health agencies; and reduced use of hospital services and judicial proceedings. Issues to be clarified in future research and practice include strategies for increasing awareness of advance directives in mental health, barriers to execution of legally and clinically effective directives, practitioners' concerns, providers' compliance with directives, effects of directives on consumers and providers, effects of managed care on implementation of directives, and stakeholders' perceptions of the value of directives.