In *Autism as Atypical Development*, Martine Delfos describes for the first time the characteristics of autism as derived from the Theory of the Socioschema, using the MAS1P (Mental Age Spectrum within 1 Person) - the spectrum of mental ages within a single person. She clearly describes how these characteristics are interrelated and how they logically follow on from one another. There are four characteristics, plus two that result from how a person with autism encounters the world and how the world encounters that person. Compared to older theories, the recognisability of these characteristics for people with autism and those around them is very high and can be translated into how to deal with them and how to prevent problems. Martine Delfos uses nearly 100 real-life examples to show what atypical development looks like in everyday situations and at different ages.By her own account, she has never been so clear in her explanation of autism. The book also includes a chapter by John Huijbregts, a Year 7/8 special needs teacher who works with children with autism.The book is suitable for anyone with autism; although it is about them, it is certainly intended for them, their families, those around them and teachers. It is also suitable as a training manual, as it sets out the background and rationale. The book aims to provide a better understanding of autism, how it affects each individual with autism differently, and how to deal with it: in relation to oneself, in parenting and in education. Attention is paid to the workplace, but to a lesser extent, although the information provided applies to every situation.