The cognitive interview follows the same general format as the standard interview but is augmented with the following instructions given to the witness before eliciting the narrative report: reconstruct the circumstances; be complete; do not edit even seemingly unimportant information from your report; recall in different orders; change perspectives; and take on the perspective of a prominent character in the incident. Although some investigators already use one or more of these techniques, five experiments showed that the complete cognitive interview, conducted by experienced professionals, is the most effective at improving the quality and quantity of information obtained from victims and witnesses. 5 tables, 33 references.