The Crisis Intervention Team (CIT) model of jail diversion is a promising approach to addressing the over-involvement of people with mental illness with the criminal justice system. Despite its popularity and promising empirical support, the literature has yet to clarify CIT's critical elements. The aim of this study was to assess the degree to which experts agreement on the importance and perceived implementation of the critical elements of CIT. Study 1 used a literature review to cull potential elements. Three experts familiar with the CIT model reviewed these elements. Study 2 utilized an online survey of 55 CIT co-ordinators/officers and published experts to assess agreement regarding importance and degree the element is implemented. A preliminary list of 36 elements was identified with a high level of expert agreement on their importance regarding importance and implementation. This study developed a preliminary list of elements of the CIT's program. Further research should develop consensus, explore elements' association with outcomes, and differentiate elements from those common to all jail diversion programs. Copyright © 2010 John Wiley & Sons, Ltd.