In 1989, the second International Colloquium on the Middle Palaeozoic Fishes was held in Tallinn. The aim of the Colloquium was to activate the studies in fossil fish ecology, functional morphology and other palaeobiological fields of knowledge. That is why the title of the book, previously the motto of the meeting (proposed by Dr Daniel Goujet, Paris) is Fossil Fishes As Living Animals. The volume includes a significant part of the papers and posters presented at the Colloquium. The papers of the volume deal with the fossil fishes of a wide age interval, mostly from the Ordovician to the Permian, but more recent forms are not excluded either.