The studies reported here constitute part of a project on language development and social influence. The question of what to do to obtain a linguistic development that is not retarded by an unfavorable environment is discussed, relative to different value systems. In the first three chapters a theoretical background is given in which sociolinguistic and psycholinguistic theories, models and results are presented. The next three chapters describe a longitudinal investigation of 120 children, whose language abilities and socioeconomic background were studied during a nine-year period. The remainder of the book discusses the possibilities of eliminating those linguistic handicaps that are due to socioeconomic factors. Different pedagogical models are compared. It is recommended that the currently dominant pedagogy of mediation be replaced with a pedagogy of dialogue. Change in linguistic ability depending on social influences is discussed in Chapter 7. A pilot study using the "mamba" method, a new way of studying linguistic ability, is described in Chapter 8. Chapters 9 and 10 provide a summary and discussion. (Author/RM)