Fletcher who led Zimbabwe to their memorable 13-run win over Australia in the 1983 World Cup and coached the South African A team on their tour of England last summer, will be in overall charge of the first team, working closely with Matthew Maynard, who was recently reappointed as captain.
The club have been negotiating with Fletcher since last July when South Africa A played Glamorgan - and after a copy of a contract was faxed to him earlier this week he agreed to join the Welsh county.
The arrival of Fletcher and Waqar Younis, who recently signed a two-year contract, will boost Glamorgan's hopes of a successful season. Apart from their Sunday League success in 1993 they have experienced little joy elsewhere.