This half-a-day workshop took place during the Third Internation Conference on Case-Based Reasoning (ICCBR-99). Five papers were presented and there were some discussions about adaptation in CBR. The papers are: [P. Avesani and E. Blanzieri] ``Adaptation-Dependent Retrieval Problem: A Formal Definition''. [Béatrice Fuchs] ``A Knowledge-level Analysis of Adaptation in CBR'' [P. Gonzales-Calero and colleagues] ``A Subsitution-Based Adaptation Model''. [J. Lieber] ``Reformulations and Adaptation Decomposition''. [N. Neagu and B. Faltings] ``Constraint Satisfaction for Case Adaptation''.