Anyone who has spent even a little time with an autistic boy or girl soon becomes familiar with the behaviours that set these children apart. But how do parents and doctors know if a baby has autism? Early diagnosis has proved difficult, but if it were possible, it would lead to much more effective treatment for the younger a child is the more malleable is the brain. So, the inability to detect autism until a child is two or three years old is a terrific disadvantage, as it eliminates a valuable window of treatment opportunity, when the brain is undergoing tremendous development. Researchers, however, are closing in on techniques that could detect autism in babies as young as six months and perhaps even at birth. The results of these new tests are expanding the understanding of autism and raising hopes for much earlier, specialized care that could improve a toddler’s chances for a more normal life as a child, teenager and adult.