After finishing 1½ games behind for the National League Central to the World Series champion St. Louis Cardinals, the Astros elected to a select amount of subtractions and additions to compete.
To make up for losing those key players, they signed pitcher Woody Williams, and traded with the Colorado Rockies for Jason Jennings and Miguel Asencio.
The largest offseason move the Astros made was signing outfielder Carlos Lee to a 6-year contract worth $100 million, the most in franchise history.
On April 28, the Astros purchased the contract of Hunter Pence, the organization's top prospect from Triple-A affiliate, and made his debut that night where he got his first career hit and run scored.
Longtime Astros second baseman Craig Biggio recorded his 3,000th career hit in the seventh inning against the Colorado Rockies on June 28, becoming the 27th player in MLB history to do so.
On July 28, the Astros traded RHP Dan Wheeler to Tampa Bay for right-handed slugger 3B Ty Wigginton and cash considerations.
On July 29, long time and former All-Star third baseman Morgan Ensberg was designated for assignment to make room for newly acquired Wigginton.