This paper reports on a series of studies that were conducted at the Mexican Institute of Social Security (IMSS) between 2001 and 2002 to determine the role, structure and workings of their local research ethics committees (LRECs). The IMSS, unlike other Mexican health institutions, has a formal system of committees. Such committees operate under a regulatory system and are charged with scrutinising all research proposals in order to ensure their scientific validity and to protect the rights and well being of research subjects [Instituto Mexicano del Seguro Social. Dirección de Prestaciones Médicas (México). Manual de Investigación Médica en el IMSS: Instituto Mexicano del Seguro Social; 1999]. The organisation wanted to know how the committees were functioning and if the work of the committees needed to be improved. The problems that were encountered included issues with the composition of the committees, the process of project assessment, the continuing review process, and a lack of motivation of staff. In addition a qualitative study [Valdez-Martínez E, Turnbull B, Garduño-Espinosa J, Porter JDH. Descriptive ethics: a qualitative study of local research ethics committees in Mexico, Developing World Bioethics, 2005, in press] highlighted the focus of the committees on rules, regulations and the law with little understanding of the important individual role of members in complementing and adding to these structures and perspectives. The paper suggests that, to support staff and to protect research subjects, the organizational structure, management and decision making process of the IMSS's LRECs ought to be assessed regularly through audit cycles. In order to support the further development of the committees, the aim of the audit cycles should be focused on education and development of the vision, perspectives, values, and working processes of each LREC.