The Theory of Mind (difficulty to perceive the mental states of others) is one of the most influential theories to explain ‘autistic’ behaviours. However, there is the downside of this theory – its ‘one-sidedness’ – it implies that there must be only one ToM for all people – either you develop it (and become ‘normal’), or you fail to develop ToM (and end up ‘autistic’). I’d suggest to look at a wider interpretation of Theories of Mind that may be useful not only when dealing with autistic and non-autistic populations, but also with different groups of people closely involved personally or professionally. 
The Triad of Impairments (Lorna Wing) was widely used for diagnosis of autism. However, it turns out to be useless in dealing with autistic individuals on a daily basis. The Triad of Perspectives on autism considers the condition from three different points of view – autistic, parental and professional ones’. The analysis of this unconventional notion brings a completely new interpretation that could be used in creating ‘autism-friendly environment’ and comfortable co-operation of these three groups of people.