His script for the film Three Thousand was accepted by the Sundance Institute in the late 1980s. Executives at Touchstone Pictures, a division of The Walt Disney Studios, became interested in making the movie. He changed the title to Pretty Woman, and with over $400 million in worldwide box office, the movie became the largest grossing live-action film in Disney history. Directed by Garry Marshall, with Richard Gere and Julia Roberts, the film is a story about Vivian Ward, a prostitute who is hired by a wealthy businessman, Edward Lewis, to be at his beck and call for one week while he is in town on Business. Although they come from different backgrounds and lifestyles, they end up developing a relationship based more on genuine love than money and convenience. Pretty Woman was a huge success and got Lawton nominated for a Writers Guild of America Award and a British Academy Award for his screenplay. Julia Roberts won a Golden Globe Award for her role and was nominated for an Academy Award for Best Actress.

With Barry Primus, Lawton co-wrote Mistress, a comedy starring Robert De Niro, Danny Aiello, Christopher Walken and Martin Landau. The movie is about a Hollywood Screenwriter, Marvin Landisman, whose career is going downhill until he meets a has been hustler-producer who tries to help him get his career back. Starring an all-star cast, Mistress was one of the first films produced by Tribeca Productions, Robert De Niro's production company, and it was released in the summer of 1992.

For Columbia Pictures he co-wrote the 1994 film Blankman, a film starring and produced by Damon Wayans who plays Darryl, a nerdy, comical ghetto superhero with a pure heart ready to fight Criminals in his own style. The film also stars Jason Alexander, who previously had worked with Lawton in Pretty Woman, and Greg Kinnear early in his career.

Lawton went on to write and direct The Hunted (1995), a thriller set in Japan starring Christopher Lambert, John Lone and Joan Chen. Written and directed by Lawton, the movie traces Paul Racine, a computer-chip executive from New York in one of his many Business trips to Tokyo. Local authorities and a legendary ninja cult get involved in an electric chase after a crime occurs in a hotel room. The Hunted was released on February 25, 1995 and distributed by Universal Studios. The score, featuring music by acclaimed Japanese taiko troupe Kodo, was especially requested by Lawton.

Lawton's next film project was the 1996 action thriller Chain Reaction, which starred Morgan Freeman, Keanu Reeves and Rachel Weisz. Filmed in Chicago, Illinois, the movie was released on August 2, 1996, and grossed over $60 million worldwide.

In 1998 Lawton created and executive produced Sony Pictures Entertainment hit syndicated show V.I.P. through a successful four-year run until 2002. The adventure series starred Pamela Anderson as Vallery Irons, a small-town girl who comes to Southern California looking for a break when she stumbles into the glamorous role of heading up a Beverly Hills bodyguard agency called Vallery Irons Protection. The series saw Anderson often poking fun at her tabloid image,

In 2006, Lawton co-wrote for Paramount Pictures a film based on the video game series DOA: Dead or Alive, starring Eric Roberts, Jaime Pressly and Devon Aoki.

Lawton wrote and directed the 2008 film Jackson, a comedy-drama-musical starring Barry Primus, Charlie Robinson, Steve Guttenberg, Debra Jo Rupp and opera Singers Ella Lee, Shawnette Sulker and Clamma Dale. The movie takes place on a single day involving two homeless men surviving on Los Angeles's Skid Row. Lawton wrote two songs for the movie, "Downtown Birthday" and "Love Cannot Be". Jackson was shot mainly in Downtown Los Angeles, except for one scene shot in Kentucky.