This book has been developed for those who wish to increase their understanding of technical and scientific English. It is designed especially for Spanish-speaking students, scientists, and technicians who are preparing to take courses in American schools or under instructors abroad. The 50 reading selections are drawn from a wide variety of technical, semi-technical, and scietific writings. They cover a broad range of subjects, and because no definite sequence is intended, they may be selected for study in any order. Selected specifically for vocabulary content, the readings are also self-expository. Lexical items of a technical nature or with specialized contextual meaning are defined in Spanish in the margin of the page on which they appear. Exercises follow each reading selection. Comprehension exercises develop overall understanding as well as mastery of specific sentences. Vocabulary exercises reinforce understanding and strengthen retention of newly acquired words. Conversation exercises provide active oral practice. Answers to the exercises appear at the end of the book. (Author/AMM)