He made his first-class debut in January 1999, opening the batting for the Windward Islands in a Regional Four Day Competition match, he made low scores of 12 and 4 in a heavy defeat to Barbados. His first half-century was brought up in his third match of the season, scoring 79 in the first innings against the Leeward Islands. It was the only time he passed 50 runs in his debut season, finishing with a batting average of 18.44 from nine innings, which is considered low for a specialist batsman. His average remained around that level over the following two seasons. Despite his relatively low scoring, he was picked to play for the West Indies A team against South Africa A in September 2000, making scores of 14 and 23 in a drawn match. In the 2000–01 season Smith was part of the Windward Islands team that won the List-A West Indian domestic competition for the second time in their history.

The 2001–02 marked a significant improvement in Smith's form, he made 841 first-class runs at an average of 64.69 and scored his first century. A successful tour of England with the West Indies A team followed, yielding 465 runs at an average of 46.50.

In June 2018, he was named the Best Regional Four-Day Cricketer of the Year at the annual Cricket West Indies' Awards.

Smith made the step up to international cricket when he was selected in the West Indies squad to face Australia in their 2003 tour. He made his Test debut in the first match of a four-Test series at Bourda, a score of 3 in the first innings was followed by 62 in the second, in a match that Australia went on to win by 9 wickets. Despite scoring a pair in the second Test, Smith retained his place for the rest of the series, making another half-century in the third Test. Smith also made his ODI debut on the same tour, he played the first three matches of the seven-ODI series, making a highest score of 26.

After being dropped from the West Indies team for their 2003–04 tours of Zimbabwe and South Africa, Smith regained his place for England's tour following an impressive domestic season, where he was the leading batsman in the Regional Four Day Competition, scoring 842 runs at an average of 76.54. His good form continued into the first Test of the series, where he made 108, described as a "gritty effort laced with occasional panache", his first Test century. Smith was unable to play in the final two matches of the four-Test series after fracturing his thumb while practising in the nets.

From May 2004 to June 2005 Smith played six Test matches, failing to reach a half-century in that time. During the 2004 tour of England he played three ODIs in the NatWest Series, where he made a highest score of 44, it was his last appearance for the ODI team until January 2007. Smith made a slight return to form in November 2005 against Australia in Brisbane. In a heavy defeat he was the only West Indies player to score a half century, making 88 in the first innings. Despite this Smith did not perform well in the rest of the series and again lost his place in the side.