The City of Vienna keeps three folio-volumes of a manuscript in conservation of her archive, which in common was marked as Viennese "Testamentsbücher" (analogous: Viennese Last Wills-Register). The source, originated in the late Middle Ages, originally was called "Stadtbuch", and this character indeed appoints her to such registers, which served for registration of legal transactions in urban space. By no means she only embodies last wills (so called "Geschäfte"), but also a lot of registrations about other transaction concerning matters of private law (for instance sharing out a succession, taking of evidence about the family relationship or the majority of age of persons; declaration of claims descended in the state of emergency) and other registrations about transactions concerning matters of pubic law (for instance the panels of the members voted on town council, town councils ordinances and regulations about urban handicrafts). The registrations comprises the period of 1395 to 1430. Systematic investigationes on the source have been submitted only to single questions in the area of legal history and concerning aspects of material culture: By this way parts of registrations have been quoted and interpreted, but only a few were published - partly in form of regesta, partly in full wording. The Viennese "Stadtbücher", representing a source of law of first order, haven`t relevance only to legal history, but also to other departments of science - to mention a few: History of culture, society and economics. The sources importance as a "Stadtbuch" concerning one of the most important towns in Central Europe is beyond the local scope. Therefore the entire edition source seams to be usefull; only by this way it will serve the interests of all historians. To standardize each registration remarks in legal history are placed in the front of it, for the rest the content largely has been edited in full wording. The forurth part of the Viennese "Stadtbücher" comprises the registrations in the space of 1412 up to 1417; a continuation in further deliveries up to 1430 is considered. The last part will contain exhaustive descriptions on the original manuscript and detailed critical comments about the method of edition, just as extensive indexes. Until the edition will be finished an index of registrations and a glossary containing historical explanations on legal terms and contemporary institutions of legal life for this edition will serve for guidance.