When we engage in the systematic follow-up of high-risk neonates it is important to avoid the temptation to assume that any variations in development in this population reflect 'abnormality.' In this chapter I first present some personal reflections and hobby horses to argue that we need to be aware of our possible biases toward interpreting developmental or functional differences in infants as evidence of developmental pathology. Second, I stress the challenges associated with making early 'diagnoses' of developmental disabilities. Instead I suggest that identification of differences and variations in development should be interpreted cautiously, taking account of natural variations in early development and the chance to observe children over time rather than needing to make a decision on the basis of a single assessment. Finally, I discuss cerebral palsy and illustrate the arguments I have presented with discussion of current thinking about diagnosis and classification of CP.