Density functional theory (DFT) was used to study polymer chains, tethered to a surface and in the presence of a solvent. For reasons of computational practicality, it is common practice to remove the explicit solvent molecules from the problem. Contact was made with two such models, which we call the "`implicit-solvent" and "continuum-solvent" approximations. First, DFT was applied to tethered chains in an implicit solvent. Using the equation of state of bead-spring chains as input, we found excellent agreement of the theory with density profiles obtained in molecular dynamics simulations on the same model as a function of temperature. Next, DFT was applied to tethered chains in an incompressible, continuum solvent. Using the Flory-Huggins theory as input, our DFT equations reduced to conventional self-consistent field theory. From our DFT formalism, we demonstrated that the implicit-solvent problem, at a given temperature, is equivalent to the continuum-solvent problem, provided the chi parameter and total density are interpreted appropriately. (C) 2003 American Institute of Physics.