The therapeutic relationship is an interpersonal affiliation between a nurse and a client. It is central to the growth of interdependent psychological, emotional, cognitive, social and behavioural skills necessary for an individual’s development. The therapeutic relationship is also a fundamental component of nursing practice and a means by which nurses engage with and effect change in individuals. It predicts treatment outcome across a range of diagnoses and healthcare settings, and can become central to quality of life. This article examines the therapeutic relationship within intellectual disability nursing. It highlights the role of the nurse and the meaning of the therapeutic relationship by identifying its four building blocks: engagement, empathy, communication and trust.