A well-designed enrollment process ensures appropriate selectivity of subjects from within the population responding to recruitment efforts. The quality of this process can be documented only by careful recording of interactions with patients who were ineligible or who refused to join the study. Detailed documentation of these encounters serves medical-legal purposes as well since the majority of interactions with patients reveal some findings of medical import. These records further serve as a source of potential subjects for studies that the team may choose to undertake at a later date. This chapter will outline methods of storing records of excluded study candidates that permit these objectives to be achieved most expeditiously.