Polymers are modified by femtosecond-(fs)-IR-laser irradiation under various process parameters. Several sorts of thermoplastic polymer are employed: polymethylmethacrylate (PMMA), fluorinated PMMA, poly-N-methyl methacrylimide (PMMI), polystyrol, polycarbonate, polyimide, and polyethylene. After the fs-laser-induced modification process, the irradiated area is developed by an aqueous solution of a solvent agent (n-hexane, benzene, and methylisobutylketone). The surface topography of the fs-laser-irradiated area is characterized by stylus-profilometry before and after the development procedure. Some preliminary explanations are given about the solution mechanism of the fs-laser-irradiated polymer region. The experimental results are relevant for the fabrication of three-dimensional (3D)-structures in the volume of a transparent polymer material by fs-laser irradiation. (c) 2006 Wiley Periodicals, Inc.