The distinction between friends and acquaintances is often made in everyday conversation but the significance of this distinction is under-explored. Acquaintanceship can be understood as a form of knowledge of other people that lies somewhere between intimates and strangers. This book argues that acquaintanceship is a topic worthy of investigation in its own right and assesses the overall significance of acquaintances in late modern society. This fascinating book examines the topic by: exploring possible definitions of acquaintanceship; examining the key features of acquaintanceship; and, considering its nature and significance in a variety of settings. Analysing different forms of acquaintanceship - including those in places of work, neighbourhoods and between professionals and their clients - it also explores passing acquaintances and newer forms of ties such as those formed over the internet, with celebrities or even fictional characters. Soundly based in sociological theory, the book assesses the extent to which acquaintances can provide a sense of location and security in modern life and the ways in which they can provide us with insights, often fleeting, into worlds other than our own. Written by one of the foremost authorities in the field, this book is key reading for sociology students, lecturers and researchers, in particular those interested in sociological theory, social interaction, the sociology of everyday life and the sociology of intimacy.