Over the past four decades polymers containing imide groups (usually as build ing blocks of the polymer backbone) have attracted increasing interest of sci entists engaged in fundamental research as well as that of companies looking into their application and commercialization. This situation will apparently continue in the future and justifies that from time to time reviews be published which sum up the current state of knowledge in this field. Imide groups may impart a variety of useful properties to pol~'mers, e. g. , thermal stability chain stiffness, crystallinity, mesogenic properties,...