No spoiler short review 

This informative book acts as a good introduction to attachment theory for people who are not familiar with the subject. It's strength is that is has lots of quizzes and exercises you can work through to better understand your own attachment style and behaviours. The reason I haven't scored it higher is due to some limitations. 1) there is less time spent on the avoidant type, and no time  at all spent on the disorganised type. 2) the examples given are exclusively heteronormative, it could benefit form being updated to be more inclusive and recognising the part heteronormativity plays in attachment theory. 3) It really is a very basic introduction to the subject and gets repetitive in the second half of the book. If you'd like to learn more about attachment theory I'd recommend next reading Daniel Siegel's works.