(FORTUNE Magazine) – It's been another disappointing fall for ABC, CBS, and NBC, which are trying to figure out why their supposed innovations (ironic yellow ads, sitcoms resuscitating faded 1980s stars) haven't worked. Maybe they should watch Fox, the No. 4 network--and the only one whose regular schedule is attracting more 18- to 49-year-olds than last year.

In September, Fox launched five new shows, while the big three premiered 29 and shuffled 20 into different time slots. Even TV insiders, let alone ordinary viewers, couldn't keep track of what was on when. The big networks also pitted similar sitcoms against one another, which splintered shrinking audiences. However, Fox, which was built on bold and edgy scheduling strategies, played it safe: It broadcast shows for audiences not served by the other networks. The gambit paid off big. Second-year sensation King of the Hill, an animated sitcom about life in suburban Dallas, has garnered top ratings for the network's Sunday lineup, and it has revived its nine-year-old counterpart, The Simpsons. Teen drama Party of Five has bloomed into a hit in its fourth season and has helped out Beverly Hills 90210, the eight-year-old show industry watchers had presumed dead. Best of all, the network has launched one of the few hits of the season, Ally McBeal, a legal drama. "We gave viewers the series they loved in the time periods they were accustomed to," says Fox President Peter Roth. "We saw a sea of chaos and countered with a strategy of calculated stability."

Fox will need new comedies to help sustain its momentum. Soaps like Melrose Place do so poorly in reruns that Fox takes them off the air in the summer; sitcoms do much better. This year execs are high on a show starring comedian Damon Wayans and produced by Carsey-Werner, the team behind Roseanne. Fox is wisely premiering this sitcom and others slowly throughout the year--instead of dumping everything in a two-week period in September and praying someone will watch.

--Henry Goldblatt