On June 28, 2007 (during the 2007 NBA Draft) the Celtics traded West to the Seattle Super Sonics, along with Jeff Green (their 5th overall pick) and Wally Szczerbiak in exchange for Ray Allen and Sonics' 35th overall pick Glen Davis.
He was reunited with his Saint Joseph's teammate Dwayne Jones.
In 2005–06, West averaged 11.8 PPG, 4.1 RPG and 4.6 APG.
On February 12, 2006, he was named to represent the Celtics on the sophomore team for the Rookie Challenge at NBA All-Star Weekend.
West scored all 31 of his points in that game during the second half and the two overtimes.