This book presents the refereed proceedings of the 9th European Knowledge Acquisition Workshop, EKAW '96, held in Nottingham, UK, in May 1996. The 23 revised full papers included address the most relevant theoretical and applicational aspects of knowledge acquisition with a certain emphasis on the acquisition of knowledge for the modelling or automation of complex problem-solving behaviour. The volume is organized in sections on theoretical and general issues, eliciting knowledge from textual or other sources, data-mining, group elicitation, and planning.