While he hardly did it alone, Theo Epstein is the main architect behind the Cubs team that finally broke the most infamous championship drought in sports. He and his front office built that juggernaut of a roster through many different means, but more than anything, these Cubs were the product of a savvy string of trades.
Certainly, the Draft and international market helped, both in terms of players plucked by the previous regime (Javier Báez, Willson Contreras) and the current one (Kris Bryant, Jorge Soler). And the Cubs have not been shy about adding to their roster through free agency, bringing aboard the likes of Jon Lester, Ben Zobrist, Jason Heyward and John Lackey.
But if Epstein, the Cubs' president of baseball operations, had not been able to pull off so many lopsided trades since joining the organization in October 2011, there's little chance he could have achieved his goal so quickly.
• Epstein pads Hall of Fame resume in Chicago
Epstein arrived in town with a history of productive trades. While he had some duds in Boston -- Bronson Arroyo for Wily Mo Pena, for example -- deals for players such as Curt Schilling, Orlando Cabrera and Dave Roberts helped set up the 2004 team to break another long championship drought.
Oddly enough, Epstein's very first trade with the Cubs hasn't turned out well, as he sent DJ LeMahieu and Tyler Colvin to the Rockies for Ian Stewart and Minor Leaguer Casey Weathers. Trades of catcher Welington Castillo the Mariners last May (for Yoervis Medina) and infielder Starlin Castro to the Yankees last December (for Adam Warren) weren't exactly wins, either. Still, in both cases, the Cubs dealt from areas of strength.
For the most part, Epstein and general manager Jed Hoyer have put together a trade record about as close to flawless as is possible in such an unpredictable sport. Here is a look at the 10 swaps most crucial to the Cubs' triumphant rebuild.

10. Dec. 9, 2014: Acquired C Miguel Montero from D-backs for RHPs Jeferson Mejia and Zack Godley
For the cost of two Minor League right-handers -- Godley has pitched 111 1/3 innings for Arizona the past two years -- the Cubs landed their primary catcher for the 2015 season. While '16 did not go nearly as well for Montero, no Cubs fan will forget his two postseason hits: a go-ahead pinch-hit grand slam in Game 1 of the NLCS and a 10th-inning RBI single in Game 7 of the World Series.
9. July 20, 2016: Acquired LHP Mike Montgomery from Mariners for 1B Dan Vogelbach and RHP Paul Blackburn
Vogelbach could become a key cog in Seattle's lineup, but the Cubs are stacked with bats, and Vogelbach fits better in the American League. Montgomery turned out to be an important pickup for Chicago, especially as one of Joe Maddon's few trusted bullpen arms during the playoffs (14 1/3 innings, 3.14 ERA). The left-hander got the final out of the World Series and has five seasons of club control remaining.

8. Dec. 23, 2011: Acquired LHP Travis Wood in multiplayer deal from Reds for LHP Sean Marshall
After a nice run with the Cubs, Marshall enjoyed one more good season out of the Cincinnati bullpen before injuries limited him to just 24 1/3 more innings. Wood has gone through his ups and downs in Chicago but was an All-Star as a starter in 2013 and made a successful transition to relief last year, posting a 2.95 ERA and holding left-handed batters to a .447 OPS across 61 innings in 2016.
7. July 25, 2016: Acquired LHP Aroldis Chapman from Yankees for SS Gleyber Torres, OF Billy McKinney and RHP Adam Warren
To get their closer, the Cubs had to part with Warren and three prospects, including shortstop Torres, who now ranks second in the Yankees' system. Sure, that could sting in the long run, especially with Chapman now a free agent. But the Cubs are loaded with young infielders, and despite a couple of notable hiccups, Chapman gave the club what it needed at the back of its bullpen for the postseason. Flags fly forever.
6. July 22, 2013: Acquired RHPs Carl Edwards Jr. and Justin Grimm in multiplayer deal from Rangers for RHP Matt Garza
Third baseman Mike Olt and reliever Neil Ramírez, the other pieces the Cubs acquired, didn't work out as well. But for a couple months of pending free agent Garza, Epstein landed a solid bullpen piece in Grimm (213 appearances for Chicago), as well as Edwards. The slender righty became one of the team's best relief arms in the second half this year (13 strikeouts per nine innings, .456 opponent OPS) and isn't scheduled to reach free agency until after the 2021 season.
5. Jan. 19, 2015: Acquired CF Dexter Fowler from Astros for INF Luis Valbuena and RHP Dan Straily
Valbuena, who headed to Houston with Straily, was solid for the Astros in 2015-16, but he was an extra piece for infield-rich Chicago. What the Cubs needed far more was a center fielder and leadoff hitter, and Fowler filled those voids. Of course, Fowler also reached free agency at the end of '15. But if not for a positive experience in Chicago, he might not have returned to put together an even better encore.

4. July 5, 2014: Acquired SS Addison Russell in multiplayer deal from A's for RHPs Jeff Samardzija and Jason Hammel
A Cubs team that was not yet ready to compete had no problem giving up pitchers Samardzija (free agent after 2015) and Hammel (free agent after '14), the latter of whom re-signed as a free agent. For their trouble, they got Straily (included in the Fowler deal), prospect McKinney (Chapman deal) and the biggest prize, Russell. The 22-year-old already has produced 7.6 WAR for the Cubs and remains their shortstop of the future, with five more years of club control.
3. July 31, 2012: Acquired RHP Kyle Hendricks in multiplayer deal from Rangers for RHP Ryan Dempster
Epstein and Co. got a bit of a break when the veteran Dempster vetoed a trade to the Braves for Randall Delgado. The Cubs then couldn't match up with the Dodgers, Dempster's preferred destination, and so Plan C was finalized just before the non-waiver Trade Deadline. That took the form of infield prospect Christian Villanueva and Hendricks, whom the Cubs developed from unheralded prospect into 2016 NL Cy Young Award contender.

2. July 2, 2013: Acquired RHPs Jake Arrieta and Pedro Strop from Orioles for C Steve Clevenger and RHP Scott Feldman
For backup catcher Clevenger and rental pitcher Feldman, the Cubs got a useful bullpen arm in Strop and a project in Arrieta. The former has posted a 2.68 ERA and bunches of strikeouts in more than 200 innings in a Cubs uniform. The latter Chicago quickly transformed into a top-level starter who earned a Cy Young Award and owns a 2.52 ERA over his 98 outings with the Cubs.
1. Jan. 6, 2012: Acquired 1B Anthony Rizzo in multiplayer deal from Padres for RHP Andrew Cashner
A little more than a year after Epstein traded Rizzo to Hoyer (then the Padres' GM), the two Cubs executives found themselves on the same side of another deal. This time, it centered around Rizzo and young right-hander Cashner. While Cashner has impressed at times, he finished with just 3.1 pitching WAR in San Diego before a trade to Miami this summer and is now a free agent. Meanwhile, Rizzo became a franchise centerpiece, around which a great team could be built. Over the past three years he has produced a .913 OPS, 95 homers and 17.1 WAR, and he is signed to a club-friendly contract that could extend through 2021, including team options.