We consider a mathematical model for the quasistatic bilateral contact of a
viscoelastic body with a rigid foundation. The contact is modeled with Tre
sca's friction law with the friction bound depending on the total slip, We
present the classical as wen as variational formulations of the problem and
establish the existence and uniqueness of a weak solution. We then turn to
numerical approximations of the problem. For both spatially semi-discrete
and fully discrete schemes we show the existence of the unique solution and
derive error estimates.