The part-whole relation is an important notion in human mind that plays a crucial role in how we perceive and categorize objects in the external world as well as mind-internal representations. This workshop is dedicated to various expressions of this concept in natural language. It focuses mainly on semantic (but also syntactic) properties of part-whole structures within partitives, different types of pluralities, the mass/count distinction and event structure both from a theoretical and empirical perspective. The talks will investigate a variety of expressions referring within distinct ontological domains such as concrete individuals, eventualities and other abstract entities and offer mereological considerations based on a wide variety of linguistic evidence including data from typologically diverse languages, language acquisition and diachronic research. We hope that this event will contribute to the search of universal properties of the module of language faculty dedicated to the notion of part-whole.