BUSS® (Building Underdeveloped Sensorimotor Systems) is an innovative treatment model for children who have experienced developmental trauma. It is based on an understanding that just as a baby needs responsive, attuned and empathic relationships to grow and develop psychologically, attention needs to be given to the impact of the absence of these kinds of relationships on a child’s bodily development and regulation. The premise underpinning BUSS® is that these two processes – the need for an attuned caregiver and the progression through predictable stages of motor development – are inextricably linked; one cannot happen without the other. A case study is used to illustrate this innovation in practice, its frame of reference, methods and evaluation. Improvements were seen in physical development, parent–child relationships, cognitive functioning, self-esteem and confidence in parenting capacity. Consideration is given to how this model fits alongside therapies for children who have experienced developmental trauma and their families. This early evidence suggests that BUSS® is a clinically effective and cost-effective intervention that has positive benefits on physical and psychological development for children who have been impacted by early trauma. Further research will be required to establish both the consistency of outcomes and the mechanisms underlying its efficacy, especially in relation to psychological changes.