Our "International Research Ethics Network for Southern Africa" (IRENSA) program is unique in Africa: It offers mid-career professionals the opportunity to obtain a post-graduate Diploma in International Research Ethics by attending 3 x two-week intensive modules over one academic year, with Practicum assignments completed at their home institutions. Based at the University of Cape Town and taught by a multidisciplinary faculty with national and international reputations in bioethics, IRENSA's two-pronged program will have in 2003-2006 met all the goals it had set in our previous application. Our 49 Diploma students are REG members, scientists, clinicians, academics, government and military regulators, and researchers from the public and private sectors;they are drawn from 31 institutions, and serve on 20 RECs in S Africa and 9 in 8 other African countries. Over 100 participants are stimulated and taught at our annual two day seminar. Our goal during a renewed funding cycle will be to build on these achievements. We will continue to develop sustainable multidisciplinary expertise in the ethical, social and legal principles of international research in the cross-cultural context of low and medium-income countries in Africa, which is experiencing a rapidly increasing volume of clinical research in HIV/AIDS and other infectious diseases. Without sacrificing any of the content of our previous Diploma program, we shall expand our curriculum to include a new module on 'Global health, public health ethics and public health research ethics.'We will provide students with the concepts and skills required to effectively review proposed research on HIV/AIDS and other infectious and locally common diseases. IRENSA's renewed program will i) train 40 or more students for a Diploma in International Research Ethics;and ii) continue its popular annual two day seminar for over 100 participants. Through its unique Diploma program and annual seminar, IRENSA will continue to build the capacity of a critical mass of REC members in research ethics on the African continent. We shall follow our previous commitment to training a gender and ethnically-balanced cadre of mutidisciplinary scholars. With completion of this second cycle we will have established the basis for sustainable ongoing education and high quality performance of RECs that are essential for public health in sub-Saharan Africa.