In return, the Astros got Double-A right-hander Brendan McCurry.
Lowrie does not exactly fill a need in Oakland. Rather, he adds depth to their infield, which already includes Brett Lawrie, Marcus Semien, Danny Valencia, and Eric Sogard.
It is not clear exactly where Lowrie will play regularly, but he can fit at every infield position. It is possible that the Athletics decide to move one of their other pieces to fill a true need with the club, though it remains to be seen what is in the cards.
The 31-year-old Lowrie has bounced between the Astros and Athletics since 2012.
He spent that year with Houston, but was then dealt along with Fernando Rodriguez to Oakland for Chris Carter, Brad Peacock, and Max Strassi. After spending two years with the A's, Lowrie re-signed with the Astros in free agency. Now he heads back to Oakland in yet another trade.
Lowrie is a valuable acquisition for the Athletics becomes he comes with three years of non-expensive control. He will make $7.5 million in 2016, $6.5 million in 2017, and has a $6 million team option with a $1 million buyout for 2018.
In 2015, Lowrie hit .222/.312/.400 with nine home runs and 30 RBI in 263 plate appearances. He missed a big chunk of the season due to a torn ligament in his thumb, and after Carlos Correa's emergence at shortstop, he moved to third base when he returned.
The Astros should be able to absorb the loss of Lowrie from their lineup relatively easily, as Luis Valbuena can slide in full-time at third base. He made 85 starts there in 2015 and hit well.
The team also receives the Athletics' 30th-best prospect (via MLB Pipeline) in exchange for Lowrie. The 23-year-old McCurry posted a 1.86 ERA, 11.7 K/9, and 2.4 BB/9 between High-A and Double-A last season, making all 50 of his appearances out of the bullpen.