This book provides a summary of past and cutting-edge research on the acquisition of language by young children. It lends support to the behavioralist paradigm of language acquisition, namely, that maternal rewards and corrections should be integrated with perceptual, cognitive, and social learning conceptualizations in a skill-learning approach to explain the complexity of the language transmission and acquisition process. This latest work moves beyond to a more conceptual framework recognizing the complexity of the acquisition process. In providing this, a rationale is presented for the psychological sciences to seek rational integration among diverse theories, methods, and data in the field. This book is a systematic documentation regarding the learnability and teachability of language, with conclusions and recommendations grounded in careful observations and data. Great attention is paid to the epistemological contexts in which the research is carried out. Chapter titles include: "Broader Perspectives on Language Acquisition Research and Its Epistemological Contexts"; "Sequential Analyses in the Exploration of L1 Acquisition"; "Input and Rehearsal Frequencies as Diacritical Criteria of L1 Acquisition Theories"; "Fine Tuning in Communication and Language Training"; "Verbal Input and Verbal Learning as a Function of Lower SES Membership"; "Cultural Differences in Verbal Mother-Child Interactions and Filial Language Acquisition"; and "Evaluative Retrospect and Prospect." (KFT)