The Buffalo Bills are switching to a 3-4 defense and have turned to a man from a division rival to run it.

George Edwards, who spent the past five years coaching linebackers for the Miami Dolphins, is the new defensive chief on head coach Chan Gailey's staff.

Edwards, 43, joins the Bills after an aborted trip to the major college ranks. He was hired a month ago to be co-defensive coordinator at the University of Florida. In joining the Bills, Edwards is reuniting with Gailey. Edwards was linebackers coach in Dallas from 1998 to 2001, and Gailey was head coach of the Cowboys in '98 and '99.

Meanwhile, the Bills reached an agreement Wednesday on another big move, adding Pittsburgh pro scout Doug Whaley to become assistant general manager under GM Buddy Nix. The team has not announced that move.

Gailey suggested two weeks ago the Bills might move to a three-man defensive line. The hiring confirmed it.

"Defensively, we will start from a 3-4 alignment, but we will do what we feel is best for our players to do," Edwards said in a statement released by the team. "We are not going to give anything away about exactly what we will do, but personnel will dictate what you can and what you can't do. As far as the initial alignment, the 3-4 is what we will start off with and we will adjust from there."

Each of the top five-ranked defenses in the NFL in 2009 in terms of points allowed played the 3-4 scheme. The other three AFC East teams play the 3-4. The Bills have been a 4-3 team since 2001.

Edwards has coached for 19 years, the past 12 in the NFL.

In only one of those seasons -- with the Washington Redskins in 2003 -- did he serve as a defensive coordinator. He coached in the 3-4 scheme the past two years with Miami. His move from position coach to Florida last month was a step up, given the fact Florida head coach Urban Meyer is one of the most respected football coaches -- pro or college -- in the country. But becoming a coordinator in the NFL was a move Edwards could not turn down.

"I feel like this is a great opportunity for me to come in and have a chance to work with Coach Gailey again and the staff that he has been able to put together," Edwards said. "I am excited to have the opportunity to come to Buffalo and look forward to getting started as quickly as possible. This is a team that has played good defense in the past and I am excited to continue on with that tradition."

It's believed an agreement with Edwards has been in place for awhile. The announcement of his hiring came a day after the college signing day for high school recruits.

"He brings a wealth of experience, not only as a motivator and communicator, but he has been involved with some great schemes and we are excited about him being the head of our defense," Gailey said.

The 3-4 scheme will be a big adjustment for the Bills. They do not have a prototypical nose tackle for the 3-4 scheme. They could use at least a couple 250-plus-pound outside linebacker candidates to bolster the pass rush. Aaron Maybin, last year's first-round draft pick, will switch from defensive end to rush linebacker in the 3-4 scheme. The Bills have one linebackers coach, Giff Smith, on staff, and may hire another.

Edwards' one year as defensive coordinator in 2003 was head coach Steve Spurrier's final year, and it was unsuccessful. The Redskins ranked 25th in yards allowed. They were fifth the year before and third the year after. Washington had a different defensive chief six years in a row, from 1999 through 2004.

Linebacker LaVar Arrington made the Pro Bowl for the 'Skins in 2002 and 2003 under Edwards.

"He understands the needs and concerns of working with players," Arrington said. "I think it's an awesome pickup for the Buffalo Bills. I might come back and be a linebackers coach now, man, that's how much I think of him."

The Redskins fell apart in 2003 as Spurrier grew increasingly disenchanted with the NFL game.

"It was his first year, but there wouldn't have been many coaches who could have gotten results that year in that environment," Arrington said. "There was a lot going on. It was Spurrier's last year. It was almost as bad as it was this year there with Jim Zorn. You can't put that one on George Edwards. He had an uphill battle. But the dude knows his stuff."

Arrington says the 3-4 will be good for Maybin, with whom he's friends.

"He'll be good for a lot of those guys in that defense, especially my guy, because I think he needs to be a linebacker in the NFL," Arrington said.

Meanwhile, the addition of Whaley comes in the wake of the Bills' firing of John Guy as pro personnel director two weeks ago. Whaley becomes Nix's right-hand man.

Whaley has spent the past 10 years as Pittsburgh Steelers pro scouting coordinator and has been identified in league circles as an up-and-coming general manager candidate the past couple of years.

Whaley was a homegrown talent for the Steelers. He graduated from Pittsburgh's Upper St. Clair High School in 1990 and played college football at the University of Pittsburgh as a safety and linebacker.

He broke into scouting in 1995 as an aide with the Steelers. Then he spent three years as an area scout for the Seattle Seahawks before returning to the Steelers. He was responsible for evaluating pro players and advance scouting for Pittsburgh, the same role that Guy filled in Buffalo since 2001. Whaley evaluated the strengths and weaknesses of opposing players and provided a report each week as part of the team's pregame preparations. He also did some scouting of college games for the Steelers each fall.

The Steelers have one of the most respected scouting operations in the NFL, which is a big reason Whaley has been mentioned as a prospect for a promotion.

Pittsburgh's best success in free agency has been identifying which veterans to retain. The Steelers have done a great job of keeping their own young talent. Their key free-agent signings during Whaley's tenure have been Pro Bowl linebacker James Farrior, center Justin Hartwig, safety Ryan Clark and defensive tackle Chris Hoke.