Before considering in breadth the diverse contributions that structure brings to building exteriors, this chapter begins by examining one building more deeply: the Hong Kong and Shanghai Bank, Hong Kong. A study of the exposed structure on its main facade sets the scene for discussing many of the roles exterior structure plays. The chapter presents case-studies which illustrate how the structure modulates surfaces and provides a means for introducing often much-desired depth and texture. It also examines the aesthetic quality of exterior structures in more detail. Structure also screens facades, and filters light and views. The importance of suitable structural scale is noted where structure plays any of these roles. The chapter explores how structure connects exterior and interior architecture, and how it marks and articulates entry into a building. It provides precedents of structure playing expressive roles.