mi2b2 aims to facilitate searching, acquiring, and previewing radiological images stored in multiple PACS (Picture Archiving and Communication System) systems. It is an intermediate layer between a user and the PACS, which may be housed across multiple institutions (e.g. hospitals or research institutions) and departments (e.g. radiology, cardiology, or neurology). mi2b2 has a server component that connects to PACS and a client component via which user interacts with the server. In this document, the server component will be referred to as the "mi2b2 server" or the "Star-D server." The interface by which users will search, acquire, and preview the radiological images will be referred to as the "client." This document describes the functionalities and usage scenarios of the client.