The factors are investigated which influence adhesive strength when bonding PS, impact PS, and acrylic butadiene styrene with the aid of various solvents. The most important of these factors are the polarity of the phases and the diffusion. Compared with glue bonds the surface tension and wetting between the phases are of less importance with solvent bonding whereas the swelling of the plastic and the boiling point of the solvent have a great influence. The suitable solvents for bonding PS plastics are suggested.