Martha Virginia Pennino, 86, a former vice chairman of the Fairfax County Board of Supervisors who was known as "Mother Fairfax," died yesterday at Inova Fairfax Hospital. She had Parkinson's disease.

From 1968 to 1991, Pennino was at the center of nearly every major decision made in Fairfax County, the area's largest jurisdiction. Representing the Centreville District, she became a symbol of the emerging Fairfax at regional meetings.

She left her mark on nearly every corner of the district -- which stretched from Vienna to Reston out to Dulles International Airport -- including such projects as the Dulles Toll Road, Reston Hospital Center, South Lakes High School, the Reston Community Center and the Reston Regional Library.

Pennino, a Democrat, played an instrumental role in the planned community of Reston, which was taking shape when she took office. She also maintained a commitment to the poor and the homeless. She once put cots in her supervisor's office and opened it at night to people with nowhere else to go. She also pushed for a shelter for the homeless in her district, and supported building low-cost housing and buying and renovating the run-down Stonegate apartment complex.

She supported much of Fairfax's rapid growth during the late 1970s and 1980s. But in the mid-1980s, when county officials began to feel the backlash from county residents about rapid development, Pennino issued a call for a one-year freeze and criticized some developers as "greedy."

She was a driving force in the establishment of the Fairfax County Human Rights Commission. In 1994, the board dedicated the Fairfax County Human Services Center in her name at 12011 Government Center Pkwy.

Pennino, known for her bouffant hairdo and warbly voice, spent 24 years on the board, serving as vice chairman for 17 years.

"My mother was a humanitarian,' " said Pennino's youngest daughter, Bonita Pennino. "She worked diligently to make sure that every county resident could benefit from everything that Fairfax County could offer."

Pennino's career on the Fairfax Board of Supervisors ended in 1991, when she lost her bid for a seventh term to Republican Robert B. Dix Jr. A 1991 Washington Post article gave two contrasting views on what contributed to her defeat: voter discontentment with the political establishment, and her own arrogance after having been in office too long.

Pennino initially said she was a little sad about losing, then confessed to being somewhat depressed. But then, she told a Post reporter: "I've lived through cancer, lived through polio, lived through wars. Certainly, the fact that I wasn't reelected isn't a tragedy."

Pennino was born in Roanoke and raised in Glocester, Mass. She received a bachelor's degree from Emerson College in Boston.

She received many accolades for her work in Fairfax. In 1985, she was awarded the Tom Bradley Regional Leadership Award from the National Association of Regional Councils. The group cited her efforts in developing the first energy policy for a metropolitan area, the region's car-pool program and a fair-share housing program. In 1986, Washingtonian magazine named her "Washingtonian of the Year."

Before joining the county board, Pennino was elected to three terms on the Vienna Town Council.

She also was involved in many community boards and foundations. She was a member of the advisory board of the Northern Virginia Youth Services Coalition, director of the Northern Virginia Community Foundation and a commissioner on the Northern Virginia Regional Commission. She also sat on the Board of Visitors of George Mason University.

She was president of the Virginia Association of Counties of the Virginia Municipal League. She also was a member of the board of directors of the Metropolitan Washington Council of Governments for 17 years and held the posts of president and chairman.

Her hobbies included gardening, flower arranging, golf and tennis.

Her husband of 57 years, Walter A. Pennino Sr., died in 1998.

In addition to her youngest daughter, who lives in Fairfax County, survivors include three other children, Walter "Penney" Pennino Jr. of Fredericksburg, Angela Curly of Larkspur, Calif., and Donna Howard of Honolulu; nine grandchildren; and eight great-grandchildren.

Martha Virginia Pennino, who died at 86, had been vice chairman of the Fairfax County Board of Supervisors.In 1995, Martha Pennino, right, helped celebrate the election of School Board member Robert Frye Sr. and Board of Supervisors Chairman Katherine K. Hanley in Fairfax County.