Differential argument marking is an umbrella term for languages encoding the same grammatical function, such as the subject or the object, in different ways. It consists of non-uniform encoding of arguments in relation to grammatical case marking, and in terms of the presence or absence of agreement on the verb. There are several sub-types of differential argument marking based on the grammatical function or the semantic role of the differentially-marked argument. These sub-types are differential subject marking, differential object marking, differential agent marking, differential recipient marking and differential theme marking. This book traces the progress of this field and highlights some of its key concepts and applications. Different approaches, evaluations, methodologies and advanced studies on differential argument marking have been included herein. A number of latest researches have been included in this book to keep the readers up-to-date with the global concepts in this area of study.