The motivation for this panel and debate grew out of discussions held in Session # 2 at the Third Annual Workshop on Empirical Studies of Software Maintenance, WESS '98, Session # 1 Bethesda, Maryland, November 16, 1998 that dealt with the topic: "What are the differences between maintenance tools tools/methods/skills and those of development". This session had the following participants: A. von Mayrhauser (chair), B. A. Kitchenham, F. Niessink, N. Schneidewind, J. Singer, G. H. Travassos, S. Takada, R. Vehvilainen, and H.Yang.Subsequent to WESS, Barbara Kitchenham and Anneliese von Mayrhauser discussed the possibility of our group producing a paper on the Ontology of Maintenance. Then a technical report was published on the subject [1]. This paper is based largely on the ideas expressed in that report.