This paper will introduce the ‘Psych-Aetiology Graph’, PAG for short. The concept of PAG is devised by the author as a way of conceptualising/formalising/summarising the client’s condition. The term ‘Psych-Aetiology’ is used to encompass all the Bio-Psycho-Social factors contributing to the client’s presenting condition. Also, the graph has no arithmetic value and is not based on any particular measurements or calculations. The target of the PAG is the client. Its main aim (amongst many) is to educate and give the client an understanding of factors resulting or contributing to their state. It is subjective, whereby the client and the therapist must cooperate in its formation.