South Africa cricket captain Graeme Smith has joined Surrey as their new skipper with \"immediate effect\", the English county announced on Thursday. Smith, currently leading the Proteas on their tour of Australia, will join Oval-based Surrey after the conclusion of South Africa\'s home series against Pakistan in March -- ahead of the start of the 2013 English domestic season. The move, on a three-year deal, to the First Division club is bound to lead to speculation regarding Smith\'s international future. The 31-year-old opening batsman has been captain of South Africa since 2003 and this year led his country to the top of the world Test rankings after a series win in England. He replaces Rory Hamilton-Brown who stood down as Surrey captain, and who has since joined Sussex, following the death of his friend and team-mate Tom Maynard in June.