Language development in disadvantaged children and the research related to this area are the subjects of this issue of the IRCD Bulletin. The first part discusses the functions of the various components of language and the effects of language deprivation on disadvantaged youngsters. The educational approaches to teaching language fundamentals which is proposed here implies that correction of pronunciation and grammar should be de-emphasized at the primary grade level. The second part notes the various research approaches to the study of language development--cross-sectional comparisons of social class differences, studies of fundamental processes of language acquisition, and the monitoring of language. Other research orientations include studies of language as a class of metiational behavior, as a social class communication pattern, as interpersonal communication, and as a social dialect. An extensive selected bibliography is included. (NH)