This proceedings volume contains revised and reviewed papers based on talks presented at the first International Workshop on Nonmonotonic and Inductive Logic held in Karlsruhe, December 1990. The workshop was supported by the Volkswagen-Stiftung, Hannover, and provided a forum for researchers from the two fields to communicate and find areas of cooperation. The papers are organized into sections on: - Nonmonotonicity in logic programs - Axiomatic approach to nonmonotonic reasoning - Inductive inference - Autoepistemic logic - Belief updates The bulk of the papers are devoted to nonmonotonic logic and provide an up-to-date view of the current state of research presented by leading experts in the field. A novelty in the contributions from the area of inductive logic is the analysis of nonmonotonicity in the theory of inductive learning.