He averaged 24.8 points and 9.8 assists per game as a senior and led Central Cabarrus to a 28–0 record and a MECA–6 Conference regular season and tournament title, which earned him the Meca–6 Conference Player of the Year in 2006, all-conference honors and being named Piedmont Player of the Year by The Charlotte Observer's (he also earned the last two accolades as a junior).

[2] Smith played college basketball for Wake Forest, finishing second all-time for assists in school history.

On February 24, 2011, Smith was traded to the Memphis Grizzlies along with teammate Shane Battier in exchange for Hasheem Thabeet, DeMarre Carroll and a future first-round draft pick.

[8] On December 28, he started for the Warriors in a win against the New York Knicks in place of the injured Stephen Curry, scoring 11 points, with 6 rebounds and 4 assists.

[12] On February 21, 2013, Smith was traded to the Milwaukee Bucks along with JJ Redick and Gustavo Ayón in exchange for Beno Udrih, Doron Lamb and Tobias Harris.

Smith matched his career-high in assists (along with 8 points, 2 rebounds and 3 steals) in a 116–100 win over the Milwaukee Bucks on January 4, 2014.

Smith became one of only three Suns backups since the 1980s to collect at least two 8-assist games in less than 20 minutes of playing time in a single season; the others being Jeff Hornacek and Goran Dragić.

[19] On November 7, 2014, Smith signed with the Oklahoma City Thunder to help the team deal with numerous injuries.

Oklahoma City had to use an NBA hardship exemption in order to sign him as he made their roster stand at 16, one over the allowed limited of 15.

[30] On October 26, Smith was claimed off waivers by the New Orleans Pelicans[31][32] and made his debut for the team the following day in the season opener.

In 38 minutes of action off the bench, he recorded 17 points and 9 assists in a loss to the defending champion Golden State Warriors.

[37] In his first game back for the 76ers two days later, he scored 14 points and helped the team record just their second win of the season with a 111–104 victory over the Phoenix Suns.

[40] On July 8, 2016, Smith signed with the Detroit Pistons,[41] marking the tenth team he has played for in 7 seasons.

[46] On July 9, 2019, Smith signed with the Washington Wizards, and played his first game with the team on October 23, 2019, scoring 7 points.

[49] On February 10, 2022, Smith was traded back to the Washington Wizards, alongside Vernon Carey Jr., in exchange for Montrezl Harrell.

[50] On July 6, 2022, Smith was traded, alongside Kentavious Caldwell-Pope, to the Denver Nuggets in exchange for Monté Morris and Will Barton.