Initial ventures into the search for synthetic polymers were largely motivated by factors of need rather than because of a desire to have new materials with improved properties. Thus plastics were made as substitutes for relatively rare and expensive products such as ivory, while synthetic elastomers were developed as replacements for natural rubber which became virtually unavailable to a number of nations during World War 11. In the past decade, however, immense changes in science and technology have continually placed increasing stringent requirments on polymeric materials. Commercially available products have rapidly become obsolete because of their inability to withstand decomposition under a variety of environmental extremes. As a result, the emphasis of research has changed and extensive studies have been and are currently being conducted throughout the world to find new macromolecular structures that are more useful for many new applications, particularly at high temperatures. It is the purpose of this paper to review the developments in this field during the last two years, with particular consideration given to o rgano metallic and ring-containing polymers.