Tom Joe, 64, who had served in the Nixon and Carter administrations and was an expert in social policies affecting poor, elderly and disabled people, died Oct. 2 at his home in Arlington. He had cancer.

Since 1979, Mr. Joe had been director of the Center for the Study of Social Policy, a private, nonprofit analysis and research operation. In that capacity he promoted programs for children, families and the disabled at the federal, state and local levels. He helped the Kids Count initiative, which is the annual publication of data indicating the status of children's well-being, state by state.

He was born in Milwaukee. He had been blind since early childhood. He graduated from the University of California at Berkeley, where he also received a master's degree in political science.

He began his professional career as a staff member of the California Assembly, where he was a welfare rights advocate and a supporter of financing strategies to increase health and human services. In 1969, he came to Washington to help develop President Richard M. Nixon's Family Assistance Plan. Later, he was an adviser on domestic policy to President Jimmy Carter.

Mr. Joe was influential in shaping the Supplemental Security Income Program and the earned income tax credit to supplement the incomes of the working poor.

In 1986, Mr. Joe received a MacArthur Foundation "genius" award. He was the author of policy papers and articles and, with his wife, Cheryl Rogers, wrote the book "By the Few, For the Few: The Reagan Welfare Legacy."

He was a member of the National Institute for Handicapped Research, the National Panel on Disability and the board of directors of the Center for Mind-Body Medicine.

Survivors include his wife, of Arlington, and four children, Leslie Joe of Arlington and Melanie, Stephanie and Jonathan Joe, all of Washington. A son, Andrew Joe, predeceased him.