This chapter does not present new findings but takes a different slant on the research that has been reported in previous chapters. The slant is that of considering what taking part in such research can do for the student. Obviously not all cognitive research is illuminating to the participants who take part in it. If you are the participant in a reaction time or a gaze duration experiment (e.g., Just & Carpenter, 1980) you may be providing data that are ultimately of great theoretical importance, but the variations in behavior that produce these data are probably too minute for you to detect and, unless you were versed in the underlying theory, you would not know what to make of the variations if you could detect them. But the participants’ situation is quite different in research that requires them to judge, predict, justify, or to verbalize their thoughts. Here participants can monitor their own behavior and may be surprised, puzzled, or enlightened by what they observe. Moreover, what is enlightening to the participant is likely to be enlightening to the researcher, and vice-versa. Thus there is the possibility of a kind of collaborative investigation that is beneficial to all parties.