This volume contains papers from the Workshop on Incompleteness and Uncertainty in Information Systems, which was held at Concordia University, Montreal, Canada, from 8 - 9 October 1993. The workshop was organised by the University's Software Engineering and Knowledgebase Systems (SOFTEKS) Research Group. It attracted participants from a wide variety of backgrounds, including those doing both fundamental and industry-oriented research into databases, software engineering and AI in North America, Europe and Asia. Amongst the actual topics covered in this volume are: software aberrations - origins and treatments; modeling uncertainty in object-oriented databases; management of uncertainty in AI - a rough set approach; uncertainty as a function of expertise; a relational data model for manipulating probabilistic knowledge; and unnesting fuzzy SQL queries in fuzzy databases.