Investigators faced with overwhelming subject response may need to employ a strategy for determining who among the eligible subjects will be considered for participation. This is particularly true for studies evaluating a therapeutic intervention where the potential benefits of the intervention show great promise. In cases where more individuals are eligible to participate than can be accommodated by the available resources within the research project, the investigator may utilize other methodologies such as a lottery (a system of random selection) or queuing (first come, first served) to select subjects. A system of random selection is often the preferred approach because it removes any selection bias and ensures that all potential subjects have an equal chance to participate in the study. No matter what method is used, its impact on the timing of selection should be considered. Timing of selection is very important to some potential subjects, such as those who are seriously ill and wish to participate in a study evaluating a promising therapeutic intervention. In these cases, a periodic, randomized selection process conducted by an impartial third party can be used to select subjects (perhaps by picking names out of a hat) from the pool of all potential subjects meeting the inclusion criteria. The selected subject(s) would be offered participation first, and if they decline, additional names would be drawn until all slots are filled. Although the theoretical basis for using a random method of subject selection, such as a lottery, is sound, it is not often utilized.