This book really does three things. Firstly, it provides a critique of a lot of social network research. Essentially the research is not theoretically driven and fails to recognize that networks can be analysed at different levels - for instance in terms of individual nodes, in terms of dyads or triads or at a global level. Researchers need to do a better job of sorting out what their level of analysis is and which theories are actually applicable to this level. Secondly, it provides a 150 page review of the different theoretical approaches to social networks. Thirdly, the book advocates the employment of agent based modelling to understand the development of networks. Researchers can specify a set of agents and rules about how they can interact and then run simulations to see how the network would develop. They provide an introduction to software that allows you to do this. This third strand of the book sometimes gets in the way of the other two. Despite this reservation the book does a good job of sorting out some of the complexities that anyone coming to social network research is going to discover in the literature. The book also provides an introduction to social network concepts and terminology although it is probably too brief for the complete beginner.