Use of argumentation methods applied to legal reasoning is a relatively new field of study. Many vitally important problems of legal reasoning can be profitably studied in light of these new methods, even if they cannot all be solved in any single monograph. This book provides a survey of the leading problems, and outlines how future research using argumentation-based methods show great promise of leading to useful solutions. The problems studied include not only these of argument evaluation and argument invention, but also analysis of specific kinds of evidence commonly used in law, like witness testimony, circumstantial evidence, forensic evidence and character evidence. New tools for analyzing these kinds of evidence are introduced, like argument diagramming, abductive reasoning, an analysis of conditional relevance and a new dialectical model of explanation.