The 47-year-old Goodell worked his way from a public relations intern to perhaps the most powerful job in American sports. Favored for months to get the job, he was unanimously elected by the league's 32 owners on the fifth ballot.
The son of former U.S. Sen. Charles Goodell of New York, he has been Tagliabue's top assistant, particularly on expansion and stadium construction. In 2000, he became the NFL's chief operating officer.
Goodell becomes the league's fourth commissioner since 1946.
"We've had the two greatest sports commissioners in the history of professional sports, Paul Tagliabue and Pete Rozelle, and I was fortunate to work for both of them," Goodell said. "I look forward to the challenge and thank them again for their confidence."
Tagliabue served 17 years, and during that time the league's revenues have skyrocketed. The NFL will collect about $10 billion in TV rights fees during the next six years, and enjoys labor peace with the players' association.
"Replacing Paul was not easy, and I think we've done a great job in selecting Roger," said Redskins owner Daniel Snyder. "The NFL is a complex business. Finding the right person to keep it on course was critical, and we did it."
Goodell beat four other finalists: lawyers Gregg Levy and Frederick Nance; Fidelity Investments vice chairman Robert Reynolds; and Constellation Energy chairman Mayo Shattuck III.
Goodell wasn't certain when he will assume office, although Tagliabue planned to leave the job this month.
"I believe in continuity," said Indianapolis Colts owner Jim Irsay. "It's a lot like with head coaches, and that's what Roger brings us."
Goodell's election was much less complicated than when Tagliabue was chosen in 1989. It took seven months to select a successor to Rozelle. Originally, the top choice appeared to be Saints president Jim Finks, who was recommended by an advisory committee. But many of the newer owners would not back Finks, the choice of most of the old-line owners.
It took 12 ballots over a seven-month period — six ballots on Oct. 26, 1989 — to finally elect Tagliabue.
That wasn't the case with Goodell, who was chosen Tuesday in three hours of voting.
"The process was good in that it got everyone looking ahead and not just at the circumstances in their own city," Tagliabue said.
Tagliabue simply introduced Goodell as the new commissioner Tuesday night, then stepped aside as his No. 1 aide took the podium.
"I spent my life following my passion," Goodell said. "The game of football is the most important thing. You can never forget that."