Massive Open Online Courses (MOOCs) offer the ability to educate large numbers of diverse learners who might not have access, time, or the financial resources necessary for more formal coursework. While some studies have focused primarily on understanding MOOC learners purely through their access rates to course materials, others have sought to understand learners through surveys. We combined these two sources of data to address two research questions: (1) What are the patterns of user behavior in an advanced, technical MOOC? and (2) What are the characteristics of fully engaged learners? By analyzing clickstream and pre-survey data for a nanotechnology-related MOOC, we identified differences and similarities between fully engaged learners and other groups. The lack of strong indicators to predict fully engaged learners suggests a need for improved data from pre-course surveys.