The determination of the parameters describing the shear viscosity and wall slip behavior of complex fluids, including polymer melts, polymeric suspensions, and polymeric gels, is a challenge. Here we use the squeeze flow of generalized Newtonian fluids with and without wall slip to generate an inverse problem solution methodology for the estimation of the parameters of the shear viscosity and wall slip. Analytical as well as the finite element method (FEM) based numerical solutions of the squeeze flow are used for the analysis and the determination of the parameters. It is suggested that the analytical and numerical analyses can provide the basic where withal necessary for the solution of the inverse problem of squeeze flows to characterize the shear viscosity and the wall slip parameters provided that the issues of uniqueness and stability are properly addressed. (C) 2007 Elsevier B.V. All rights reserved.