The CIT measures an examinee's comparative reaction in repeating statements about how the perpetrator committed the crime. In each listing of statements about one aspect of the crime, a true statement is concealed among false statements. The polygraph tests whether the examinee has a stronger reaction to repeating the true statement compared to reactions in repeating the false statements. The validity of the CIT depends on ensuring that the true facts about the crime included in the CIT are known only to investigators and unknown person(s) familiar with the crime. Consequently, the successful application of the CIT relies on the information derived from crime scene investigators, since this is the source of the true statements in the test. The polygraph examiner should be involved early in the investigation, since this enables him/her to obtain critical information and ensures that it is not released to anyone but those responsible for working the investigation. This article explains how to construct CITs, including a sample hypothetical test; pretest practices; how to conduct the testing; scoring rules; and decision rules. The article also notes the strengths of the CIT compared with other testing methods, as well as how it can be used as a supplement to other testing methods. In outlining the CIT's limitations, the article advises that it is a recognition test, not a deception test, in that it only determines whether the examinee knows certain information about the crime. 3 figures, 1 table, 28 references, and a 61-item bibliography