ABox Abduction in Description Logic Szymon Klarman Abstract: In this thesis we elaborate on logic-based automated reasoning tech- niques for abduction, driven by the principle of goal-oriented rea- soning. In the first part we develop two variants of a computational framework for abduction in propositional logic, based on regular con- nection tableaux and resolution with set-of-support. The procedures are proven to be sound and complete calculi for finding consistent, minimal and relevant solutions to abductive problems. In the sec- ond part we adapt the framework to the Description Logic ALC. We obtain a procedure for solving ABox abduction problems (i.e. abductive problems whose main part of the input and every solution are specified by a set of ABox assertions), for which we prove the results of (plain) soundness and (minimality) completeness.