Clark is the author of over 250 published articles and book chapters as well as three recent books - Learning from Media: Arguments, analysis and evidence. (2001, Information Age Publishers); Handling Complexity in Learning Environments: Research and Theory (2006, Elsevier) and Turning Research into Results: A guide to selecting the right performance solutions (2008, Information Age Publishers) which received the International Society for Performance Improvement (ISPI) Award of Excellence. In recent years he has received the Thomas F. Gilbert distinguished professional achievement award and a Presidential Citation for Intellectual Leadership from ISPI, the SITE Foundation Excellence in Research Award, the ASTD research study of the year award for his work on performance incentives, the Socrates award for excellence in teaching from the graduate students at USC and in 2007 he received the Outstanding Civilian Service Award from the U. S. Army for his work in distance learning.

He is an elected Fellow of the American Psychological Association (Division 15, Educational Psychology), the American Educational Research Association and the Association of Applied Psychology and is a Founding Fellow of the Association for Psychological Science.

His current research interests include the design and evaluation of instruction on highly complex tasks, cognitive load theory for multimedia and simulation training, the development of the Guided Experiential Learning training design systems for pedagogical applications and the use of Cognitive Task Analysis to capture and teach the complex knowledge used by advanced experts in all fields.