The Diagnostic Assessments of Reading with Trial Teaching Strategies (DARTTS) is a program of diagnostic tests with sample lessons in aspects of literacy. Developed by Florence G. Roswell and Jeanne S. Chall, the DARTTS program is published in a multilevel format for beginning through advanced (high school) readers. Teachers administer and score diagnostic tests and use a checklist of qualitative observations of student reading. Recording the student's highest mastery levels gives a score report for the following areas: (1) word recognition; (2) word analysis; (3) oral reading; (4) silent reading comprehension; (5) spelling; and (6) word meaning. Word analysis can also be evaluated. Trial teaching strategies, to be used as indicated by the assessment, are provided for developmental levels (beginning, primary, intermediate, and advanced). In fall 1989, approximately 1,700 students took the diagnostic assessments to establish the relative difficulty of the test items as a preliminary to a validation study with about 4,000 students using the complete program. The program is suggested for use in regular classrooms, Chapter 1 programs, special education, student placement decision making, and adult literacy programs. Sample lessons from the trial teaching strategies are included. (SLD)