The well known methods of preparation used in metallography and ceramography can, in modified forms, also be applied to plastics. Thin film preparation offers certain advantages over microtomy when processing hard, brittle, or filled plastics. The polished section technique is very suitable for composite materials, e.g. wood-plastic, metal-plastic composites, and similar technical materials. The shape, arrangement and distribution of hard fillers in the plastic material can be determined over large areas. Etched preparations are suitable for both reflected light and scanning electron microscopy. Details are given for the preparation of different plastics.