"Developmental screening" has become an invention of the generations of developmental paediatricians since the sequence of normal development was described. These descriptions were translated into scales of normal and abnormal development and applied to whole populations of children. The wide variation of "normal," the difficulty of showing it, and the poor predictive value of early developmental tests have resulted in a system with false positives and negatives. The commonsense solutionto rely on and respond to parental observationshas now been endorsed... [and is] supported...by an increasing body of research results. Those carrying out surveillance of children's development will need to move away from their crayons and one inch cubes and cultivate new skills in history taking and observation.