The first half of this publication consists of four papers presented at a 1967 working conference intended to foster the development of a theory of educational assessment. Topics discussed in "The Purposes of Assessment" by Ralph W. Tyler include assessment for diagnosis, for individual guidance, for college admissions and placement, and assessment of pupil readiness, of innovations, and of learning materials and procedures. In "Language, Rationality, and Assessment," Robert E. Stake's topics include curriculum evaluation, congruence and contingency, generalizability of findings, and rationalism and empiricism. "Evaluation as Enlightenment for Decision Making" by Daniel L. Stufflebeam includes sections on the state of the art in educational evaluation and on the nature of evaluation. The final essay by Walcott H. Beatty, "Emotion: The Missing Link in Education," focuses on self-concept, motivation, and learning and the promotion of affective development. The second half of the book is an annotated resource list of 133 instruments already developed or under development for measuring eight different categories of affective behavior. The categories and number of instruments reviewed in each are Attitude (10), Creativity (7), Interaction (15), Miscellaneous (19), Motivation (27), Personality (23), Readiness (3), and Self-Concept (29). The measures are indexed by author, title, and abbreviation. (JS)