This book covers in an encyclopedic way many aspects of the broad concept of ‘distance’. It is divided into seven parts and 28 chapters, the majority of the text dealing with a rich variety of metrics on an equally rich class of mathematical objects. Some space is devoted to entries from outside of mathematics, including concepts as foreign to quantification as for example ‘moral distance’ or curiosities like ‘Ironman distance’ or Hollywood ‘co-starring distance’ (the last one to be found in chapter 22, which is called “Distances in Internet and Similar Networks”). The title correctly announces that the book is written as a dictionary, that is, the reader is given a list of entries, each of them treated in a short and succinct way. The collection originates from a personal archive of the authors. The majority of the book is written for a reader who is familiar with technical mathematical language. At the end of the book is a list of entries but there is no index of keywords (that means for example that you will not find the Euler angle metric if looking for the keyword ‘angle’; it is listed only under the letter ‘E’). Anybody who wants a comprehensive and reliable list of different mathematical (and some non-mathematical) concepts of distance in one place (and without using Google) will find it in this book.