This book presents the findings of a research study on boys with behavioural difficulties, aged 5 to 7 years old. Boys with and without behaviour problems were told several stories with ethical dilemmas using lego-type dolls. They were asked to continue and finish each story in their preferred way. The children's behaviour was assessed in terms of aggression, intentionality and avoidance using a scoring system. The scores were analysed using Structural Equation Modelling to interpret the complex inter-relationships in their behaviour and to test the effect of demographic characteristics. The results indicate that there was an increased risk of anti social behaviour when avoidance and aggression were demonstrated in the same stories. Additionally, boys with more aggressive behaviour during the stories were more likely to demonstrate lower intentionality. This publication is written for those interested in the psychology of boys with behavioural difficulties and those with an interest in the application of Structural Equation Modelling in health research.