With 19 players due to become free agents Tuesday, it will be a busy off-season for the Bears -- whether re-signing their own players or replacing those who depart.
Arguments can be made for keeping each of the 19 or for letting them walk.
Today we'll examine the defense.
The Bears have already re-signed several of their own players to keep them in Chicago, and more could be locked up before the market opens. But they won't all be back. Others could return to the Bears after testing the waters, but it's certain that next year's roster will have a much different look.
In the NFL the only constant is change.
LB James Anderson
Bring him back: Started all 16 games on the strong side and led the Bears with 129½ tackles, was second with 7½ tackles for loss and tied for second with 4 sacks.
Let him leave: With Shea McClellin -- Phil Emery's first Bears draft pick -- moving to strong-side linebacker, guess who the odd man out is?
CB Zack Bowman
Bring him back: If Charles Tillman leaves via free agency, Bowman would be the Bears' biggest corner. He started seven games last season when Tillman was hurt and had 3 interceptions.
Let him leave: He's a capable backup, but ideally not the guy you want starting. Before last season he started just four games in the previous three years.
DT Landon Cohen
Bring him back: Career journeyman who actually started three games last season. But that was more an indictment of the Bears' defense than a testament to his ability.
Let him leave: If he's on the roster, your defense is questionable. If he's a starter your defense is a disaster.
DT Nate Collins
Bring him back: Started the first two games of his four-year career last season and appeared to be more than a capable fill-in after Henry Melton went down. Can play both tackle spots in Bears defense.
Let him leave: If Melton and Ratliff are both re-signed, Collins becomes an afterthought in the D-tackle rotation. Suffered a season-ending knee injury in Game Five.
CB Sherrick McManis
Bring him back: He was a special teams standout last season; second on the team with 15 tackles. Started one game at corner and could provide some depth at a thin position.
Let him leave: If he doesn't project as a starter or at least a nickel, which he probably doesn't, the Bears are better off drafting a player with a higher ceiling.
DT Henry Melton
Bring him back: When healthy, showed Pro Bowl talent in 2012, is one of the league's more effective interior pass rushers, and he's only 27, so he could still have some upside.
Let him leave: He's coming off a torn ACL and an alcohol-related arrest. Was not off to a good start last season and is unlikely to be 100 percent at the start of the season. Not worth the $7.8 million he made last season as the Bears' franchise player.
S Craig Steltz:
Bring him back: Long-time special teams stalwart who was third last season with 14 tackles and also has provided dependable depth, solid run defense and veteran leadership at safety.
Let him leave: Limited in pass coverage and doesn't figure to upgrade the starting lineup at a position that needs major improvement.
CB Charles Tillman
Bring him back: Who else is going to cover Calvin Johnson, the Lions' beast of a wide receiver, twice a year? If you're going to overpay for an over-30 player, Tillman makes sense because he's still playing at a near-Pro Bowl level.
Let him leave: He's 33 years old with a lot of miles on him and his best years are behind him.
S Anthony Walters
Bring him back: Walter was fifth on the Bears with 10 special teams tackles last season.
Let him leave: If he couldn't beat out Chris Conte or Major Wright for a starting job, his upside is limited.
LB D.J. Williams
Bring him back: He's a strong veteran presence with some shelf life remaining and is a known quantity in the middle who would afford last year's second-round pick Jon Bostic another year to mature.
Let him leave: He missed 10 games last season with a torn chest muscle and nine games in 2012. Besides, Bostic is ready after assuming the starter's role for the final 10 games in his rookie season.
DL Corey Wootton
Bring him back: Wootton took one for the team last season, moving from end inside because of an injury epidemic at tackle. At 6-feet-6, 270 pounds with room to grow, he can play inside or outside in a 4-3 and also fits as a 3-4 end.
Let him leave: His sacks plummeted from 7 in 2012 to 3 ½ last season and he may never be more than a versatile utility man who lacks impact as a pass rusher. He's also coming off off-season hip surgery.
S Major Wright
Bring him back: Has started the previous three years with 9 interceptions and is not shy about helping out vs. the run.
Let him leave: Missed tackles were a major problem last season, and he's never been very good in coverage.
• Coming Saturday: A look at the Bears' free agents on offense. Follow Bob's Bears and NFL reports on Twitter@BobLeGere.