The primary focuse of the research project reported in this paper over a five-year period has been on investigating the effectiveness of vocabulary teaching strategies, with particular emphasis on the two semantic-based instructional strategies of semantic mapping and semantic feature analysis. A series of five varied studies evaluated these strategies for vocabulary acquisition. All verified that these strategies are not only powerful tools for vocabulary development but good alternatives to the traditional instructional activities presented before students read a new passage (pre-reading). In this latter application, semantic mapping and feature analysis serve not only to introduce key vocabulary from a passage but also to activate students' prior knowledge of a topic, thereby better preparing students to understand, assimilate, and evaluate the information in the material to be read. In addition, when used after reading a new passage (postreading), semantic based instructional strategies provide a review of the material that anchors new knowledge to prior knowledge. In a secondary focus of the research project to determine the role of vocabulary instruction in actual classroom practice, a field survey of teachers was conducted. Results indicate that vocabulary instruction and emphasis are not high priorities with most classroom teachers. (NKA)