Abstract.A new method to impose boundary conditions for pseudospectral approximations to hyperbolic equations is suggested. This method involves the collocation of the equation at the boundary nodes as well as satisfying boundary conditions. Stability and convergence results are proven for the Chebyshev approximation of linear scalar hyperbolic equations. The eigenvalues of this method applied to parabolic equations are shown to be real and negative.Introduction.The common practice in applying pseudospectral methods to partial differential equations is to satisfy the equation at the interior nodes and to impose the boundary condition at the boundary. This procedure does not take into consideration that the differential equation is satisfied at points arbitrarily close to the boundary. In [4], one of the authors discussed the advantages of imposing a combination of boundary conditions and the equation itself at the boundary nodes, for Chebyshev approximations of the Laplace equation with Neumann conditions. Here we analyze the same idea applied to the linear hyperbolic equation