This paper summarises key activities initiated and the progress achieved between April 1993 and June 2002 in implementing the Three Rs in one of ECVAM's priority areas - the production and quality control of biologicals. These have included: organising nine key workshops; financially supporting and/or participating in a number of prevalidation and/or validation studies; financial contributions and sponsorship to relevant international workshops, symposia and conferences; and financial support for the compilation of manuals and expert reports, and training in test methods. The paper complements the papers of Hendriksen et al. and Cussler et al. included in these proceedings.