Smith was selected by the Dallas Cowboys in the second round (54th overall) of the 1993 NFL Draft. As a rookie, he was named the starter at weakside linebacker in the fourth game of the season against the Green Bay Packers, after Ken Norton Jr. was moved to middle linebacker. He registered 93 tackles (fourth on the team and led NFL rookies), 4 passes defensed, 2 fumble recoveries. His best game came in the seventh game against the Philadelphia Eagles with 14 tackles. He was named to the NFL All-rookie team and was considered one of the fastest linebackers in the league, extremely quick and versatile. He also was a part of the Super Bowl XXVIII winning team.