The book "Deontic Logic and Normative Systems" presents the peer-reviewed contributions from the 12th International Conference on Deontic Logic and Normative Systems, which took place in July 2014 in Ghent. It includes 17 revised papers and 2 invited contributions, carefully selected from 31 submissions. The topics covered range from the challenges of natural language for deontic logic to the relationships between deontic modality and other modalities, such as epistemic modality and imperatives. Additionally, deontic paradoxes, the modeling of normative concepts beyond obligation and permission, as well as game-theoretical aspects of deontic reasoning are discussed. The book offers a comprehensive analysis of the emergence of norms and their consideration from a conversational and pragmatic perspective, as well as their role in argumentation.