HIS PAPER reports on another aspect of the inquiry into the effects | of social class at adolescence, which has been carried out at the Lons don School of Economics and Political Science under the direction of Dr. H. T. Himmelweit. In an earlier paper [50 we have shown that the adolescent boys in our sample were aware of social class distinctions and had a surprisingly detailed knowledge of the social system in general. We now raise the further question: to what extent does this knowledge influence their patterns of friendship and hostility at school ? From previous writings, there is ample reason to suppose that, in the United States at any rate, there is a marked tendency towards clique formation among children of this age, and that parental socio-economic status determines admission to, or rejection by, such cliques. Warner [IO] states the problem clearly when he writes: