The process typically involves several rounds of questionnaires sent to a panel of selected experts. After each round, a facilitator provides an anonymized summary of the experts' forecasts and reasons from the previous round. Experts are encouraged to revise their earlier answers in light of the replies of other members of the panel. It is believed that during this process the range of the answers will decrease and the group will converge towards the "correct" answer. The process is stopped after a predefined criterion, such as the number of rounds, achievement of consensus, or stability of results.