Robert J. Lerner, 83, of Philadelphia, a retired mental health association leader, died Tuesday, Jan. 13, of anaplastic thyroid cancer at Penn Hospice at Rittenhouse. Anaplastic is a rare, aggressive form of thyroid cancer.

Mr. Lerner graduated from Philadelphia public schools, Temple University, and the University of Pennsylvania School of Social Work, and served in the Army from 1953 to 1955, stationed in Germany.

After earning his master's degree, Mr. Lerner became executive director of the Mental Health Association of Camden, and then of the Mental Health Association of Rochester, N.Y. In 1977, he made a final move to become executive director of the Mental Health Association of Southeastern Pennsylvania. He retired July 1, 1997. All three groups are nonprofit advocacy organizations.

Mr. Lerner led the Pennsylvania association's expansion from a small group into a multi-project, multisite organization with a staff of more than 200.

During his tenure, the association played a lead role in pressing for changes to the state's mental health system, which included closing the Philadelphia State Hospital at Byberry and developing a community-based care system for its patients.

"It is the contention of the Mental Health Association that the system has failed - not the law," Lerner said in January 1988. "We must redesign the system and provide appropriate resources for people who need services."

Mr. Lerner warned in 1989 that without enough state funds, "what should be an orderly and beneficial process might amount to simply dumping" the patients in the community. He was gratified when Gov. Robert P. Casey's administration increased funding for the community-based treatment plan, according to a news release issued at that time.

Surviving are his wife, Jean Farnsworth; daughters Rachel Lerner-Morse and Jennifer; a son, Robert; stepchildren Justine Farnsworth and Richerson Farnsworth; a sister; and eight grandchildren.

A life celebration and burial will be private.