We experimentally explore the effects of time pressure on decision making. Under different time allowance conditions, subjects are presented with a queueing

situation and asked to join one of two queues that differ in length, server speed, and entry fee. The results can be grouped under two main categories. The first one concerns the factors driving customers' decisions in a queueing system. Only a proportion of subjects behave rationally and use the relevant information efficiently. The rest of the subjects seem to adopt a rule of thumb that ignores the

information on server speed and follows the shorter queue. The second category is related to the effects of time pressure on decision performance. A significant

proportion of the population is not affected by time limitations and shows a consistent behavior throughout the treatments. On the other hand, the majority of

subjects' performance is impaired by time limitations. More importantly, this impairment is not due to the stringency of the limitation but mainly due to the

fact that being exposed to a time limitation, even to a loose one, brings along stress and panic, and causes subjects to use time inefficiently.