Snyman has represented the Springboks 36 times in a career that has frequently been interrupted by serious injuries.
In 1999 he broke his right ankle, in the act of scoring a try against the All Blacks, and when he returned – in a Super 12 curtain-raiser for DHS Old Boys in Durban – he broke the other ankle, ruling him out of the game for another long period.
But Snyman, who played on the wing in the latter stages of his Test career in 1997, fought back from his second setback and returned to Test rugby in 2001, also playing a handful of Test matches in 2002 and 2003, while also featuring for the Sharks at Super 12 and Currie Cup level.
Snyman, the most-capped midfielder in Bok history, was part of the Sharks side that went down to the Blue Bulls in last weekend's Currie Cup Final, having been dropped from the South African squad after their 52-16 Tri-Nations loss to the All Blacks in Pretoria earlier this year – some three years to the day that he picked up his first major ankle injury.
"We are extremely pleased to have signed a player of André's ability. Most importantly, he is coming to us as a 29-year-old in his rugby prime and we are looking forward to his arrival," said Leeds Director of Rugby Phil Davies.
"Our midfield has needed strengthening, especially following the departure of Braam van Straaten last season, and André has all the qualities we have been looking for.
"He has the complete package as a player, he is strong and quick on attack and a tough defender. He will add great experience to our midfield."
Leeds are currently languishing in the bottom half of the Premiership following consecutive losses to Gloucester and Harlequins and will be hoping Snyman can prove the difference against the Saints – and indeed for the rest of the 2003/04 season.