At the University of Maryland we videotaped several semesters of tutorials as part of a large research project. A particular research task required us to locate examples of students calling the teaching assistants (TAs) over for assistance with a physics question. To our surprise, examples of this kind of interaction were difficult to find. We undertook a systematic study of TA-student interactions in tutorial: In particular, how are the interactions initiated? Do the students call the TA over for help with a particular issue, does the TA stop by spontaneously, or does the worksheet require a discussion with the TA at that point? The initiation of the interaction is of particular interest because it provides evidence of the motivation for and purpose of the interaction. This paper presents the results of that systematic investigation. We discovered that the majority of student-TA interactions in tutorial are initiated by teaching assistants, confirmed our initial observation that relatively few interactions are initiated by students, and found, further, that even fewer interactions are worksheet initiated. Perhaps most importantly, we found that our sense of who initiates tutorial interactions--based on extensive but informal observations--is not necessarily accurate. We need systematic investigations to uncover the reality of our classroom experiences.