Once upon a time the broadcast design business was dominated by a firm named Pittard Sullivan.

During the 1990s the firm both revolutionized and dominated the business, before its swift exit in 2001. Pittard Sullivan was a casualty of the dot-com bust, which came as the design business underwent an equally seismic shift-from high-end supercomputers to powerful, inexpensive desktops.

Before the firm went quietly into the night, partners Billy Pittard and Ed Sullivan left an indelible imprint on the broadcast design sector. Known for creating signature brand images, the company also pioneered the move from manual, old-fashioned techniques for design to high-end digital work at many networks, according to former clients, competitors and employees.

The company was founded in 1986 at an opportune time: New cable networks were forming and innovative tools made digital design possible. Pittard Sullivan’s work was expansive and included promotions for Fox, branding for Showtime and a fully animated network ID for CBS. Its client roster included ABC, Abu Dhabi Television, A&E, CBS, CNN, DirecTV, Food Network, Fox Family, FX, HBO, Lifetime, Playboy Channel, Showtime, Starz, TBS, TNT, The Weather Channel and many others.

One of the firm’s highest-profile projects was the regular work it did with CBS from 1991 to 1998 to produce on-air network branding packages and promotion graphics for CBS. Pittard Sullivan worked closely with the network’s Michael Mischler, who was senior VP advertising and promotion at CBS and is now the executive VP of marketing at Paramount Domestic Television.

Pittard Sullivan created the on-air brand identity for CBS’s “Welcome Home” campaign in 1996. Mr. Mischler described the campaign as a new approach to branding because of the use of green-screen technology that married live-action shots to digital animation.

“It was clear to me one of the things we were very behind on was the graphic approach of the network,” Mr. Mischler said. “It was Pittard Sullivan that brought us some new ways of doing that. They created an environment for the best broadcast designers to be housed under one roof.”

Another well-known Pittard Sullivan project was the main titles for NBC’s “ER,” which combined graphics and live animation and landed the firm its fourth Emmy. The company also worked with TiVo in 1998 to develop its interface, creating what is regarded as the most intuitive and consumer-friendly digital video recorder.

Pittard Sullivan also worked with ABC to adapt its yellow and black campaign for on-air branding, using black-and-white still photography and minimally animated graphics. “It helped ABC stand out when all of their competitors were going for more of a special-effects-driven look,” Mr. Pittard said.

“They did an amazing job at creating a very different brand identity that was immediately recognizable by anyone who saw it,” said Mike Benson, senior VP of marketing for ABC, who oversaw the work with Pittard Sullivan. Pittard Sullivan’s legacy is that very idea of creating unique looks for each network, he said.

But that wasn’t enough.

“Everything kind of screeched to a halt when the dot-com bubble burst,” Mr. Pittard said.

Also, the company had expanded into interactive media, the sector most hurt by the bust. Networks pulled back on design spending and brought more work in-house. Pittard Sullivan cost twice as much as in-house designers, Mr. Sullivan said.

“It was a small business and totally impossible to do that financial turnaround in a short period of time,” he said. “Within a year, the whole dynamics of the marketplace changed rather rapidly.”

Despite the great work, Pittard Sullivan couldn’t move fast enough to keep pace with the changes as computers grew more powerful and smaller shops sprouted up without much overhead, said a former client.

The business model for broadcast design has changed completely, said Alan Schulman, who previously headed the New York office for Pittard Sullivan and is now the chief creative officer for Brand New World, which develops creative for emerging media. “You could never charge what you were able to charge before,” he said. “It can’t exist anymore.”

Still, he described Pittard Sullivan as the most creative company he worked for. “They elevated the craft of motion design into the world of real network branding,” he said.