This book presents the Ph.D. dissertation of Ilaria Canavotto. The thesis won the E.W. Beth Dissertation Prize in 2021 for outstanding dissertations in the fields of logic, language, and information. It combines modal logics of agency, counterfactuals, and norms in order to study the reasoning underlying ascriptions of causal responsibility, the responsibility an agent is subject to because of the states of affairs they have brought about. Ascriptions of causal responsibility involve both causal reasoning and normative reasoning. In order to provide a logical analysis of these components, the dissertation brings together two mainstream logics of actions, STIT (seeing to it that) logic and Propositional Dynamic Logic, and extends them with an analysis of causality, a Lewis-Stalnaker style analysis of counterfactuals, subject matter semantics, and deontic logic. The author uses the resulting logics to investigate a number of philosophical issues underlying ascriptions of causal responsibility and technical issues emerging from the unification of the above-mentioned formal frameworks.