In the introduction to my book (1962) I discussed the differences between these two syndromes, but I also pointed out where they overlapped. In the meantime various researchers, in particular van Krevelen, have made more detailed attempts to outline the differences between the syndromes, and even Asperger has revised his initial standpoint that his cases and those of Kanner are on the whole identical. Since these syndromes have in the meantime found their way into the European literature and textbooks on the subject and since they have also proved practical for everyday clinical purposes, I will discuss them here.