Watch Michael J. Fox Online

Fox's first important role was as "Young Republican" Alex P. Keaton in the show Family Ties which aired on NBC for seven seasons, from 1982 to 1989. It had been sold to the network using the pitch "hip parents, square kids," and the parents were originally intended to be the main characters. However, the audience reacted so positively to Fox's character Alex P. Keaton during the taping of the fourth episode that he became the focus on the show. This happened despite the fact that Fox only received the role after Matthew Broderick turned it down:

At the time, the show's producers felt Fox was simply too short for the gig. To make the point, NBC Entertainment Chief Brandon Tartikoff asked the show's creator Gary David Goldberg if he could imagine Fox's face on a lunchbox. Some years later, after Back to the Future, Fox's face did find its way to lunchboxes--and he was sure to send one to Tartikoff, with a note attached that reportedly read: "Dear Brandon, this is for you to put your crow on. Lots of Love, Michael J. Fox." Rumor has it Tartikoff kept the lunchbox in his office for the rest of his NBC career.

Fox met Tracy Pollan on the show when she portrayed his girlfriend, Ellen. They later married. When Fox left his next series Spin City his final episodes (Goodbye: Part 1 & 2, Season 4, Episodes 25 and 26) made numerous allusions to Family Ties. Michael Gross (Alex's father Steven) portrays Michael Patrick Flaherty's (Fox) therapist and there is a reference to an off-screen character named "Mallory." After Flaherty becomes an environmental lobbyist in Washington D.C., he meets a "conservative congressman named Alex P. Keaton."

Fox married actress Tracy Pollan on 16 July 1988, at West Mountain Inn in Arlington, VT. The couple have four children: Samuel Michael (born May 30, 1989), twins Aquinnah Kathleen and Schuyler Frances (born February 15, 1995), and Esmé Annabelle (born November 3, 2001). Fox holds dual Canadian-U.S. citizenship.

Fox started displaying symptoms of early-onset Parkinson's disease in 1990 while shooting the movie Doc Hollywood, though he wasn't properly diagnosed until the next year. In 1998, he decided to go public with his condition, and since then he has been a strong advocate of Parkinson's disease research. His foundation, The Michael J. Fox Foundation, was created to help advance Parkinson's Disease research through embryonic stem cell studies.

One of the few people to know that Fox had Parkinson's Disease before 1998 was one of Michael's best friends, his stunt double Charles Croughwell on Doc Hollywood. In later years, he and Fox developed a system of hiding Michael's symptoms.[citation needed]

In 1998, he was honored with a star on Canada's Walk of Fame.

On May 14, 2008, Fox was the recipient of an honorary degree, Doctorate of Fine Arts at New York University's 176th Graduation Commencement, the only college graduation to be held for the first and last time at Yankee Stadium in New York, NY. Later on May 22, he received the degree Doctor of Laws honoris causa from the University of British Columbia.

Fox, in a 2006 interview with Katie Couric, explained his political advocacy, "I'm in this situation with millions of other Americans... and we have a right, if there’s answers out there, to pursue those answers with the full support of our politicians".

Two years earlier, Fox had appeared in a television commercial for Republican Arlen Specter's 2004 Senate campaign. In the commercial, sponsored by Specter's re-election campaign, Fox comments that Specter "gets it" and Specter's voice is heard saying, "There is hope."

On July 18, 2006, Fox appeared in a taped interview on ABC's Good Morning America, defending a Senate bill (Stem Cell Research Enhancement Act) that would have expanded federal funding for stem cell research. The bill was not enacted, however, being vetoed by President George W. Bush.

For the November 2006 U.S. midterm elections, Fox endorsed candidates on the basis of their support of embryonic stem cell research, as different from adult stem cell research. He appeared at events for several candidates including New Jersey Senator Bob Menendez, Iowa Secretary of State and gubernatorial candidate Chet Culver, Illinois congressional candidate Tammy Duckworth, Virginia senatorial candidate James Webb and Ohio senatorial candidate Congressman Sherrod Brown.