This study provides a description of personal and professional characteristics of secondary school science teachers who have participated in an Academic Year Institute (AYI) program sponsored by the National Science Foundation. Pre-institute participant characteristics were determined from application forms, while the post-institute characteristics were determined from a questionnaire mailed to 72 participants. From the 58 responses, tabulation and analysis of frequency of occurrence and percentage provided the desired descriptions. The instrument used to determine any relationships in the data was the Institute Objectives Scale (IOS). Personal characteristics included: male-female ratio, 2.5 to 1; married-single ratio, 2.7 to 1; and average age, 31.6 years. It was concluded that the objectives of the AYI were achieved by a majority of the participants. The AYI influenced the participants to increase their mobility, leadership roles, professional activities, and professional status. (Author/EB)