BelTox organized an advanced toxicology course on “Embryo-fetal Developmental toxicity Testing” on 25th October 2017 at the WIV-ISP in Brussels. Fifty participants attended the course and came from Belgium, The Netherlands, Germany and the United Kingdom. The speakers and coaches for the practical exercise were experienced toxicologists from academia, industry, government institutions and consulting. The morning session chaired by Philippe Vanparys (Gentoxicon) started with a presentation on the biology of embryo-fetal development in rats and rabbits and how this relates to humans (Steven Van Cruchten, UAntwerpen). Thereafter, in vivo testing of embryo-fetal development in rats and rabbits was presented (Birgit Peter, Charles River) and the relevance of findings in these species to humans was discussed (Dirk Mariën, Janssen Pharmaceutica). The morning session ended with a presentation on the regulatory aspects of embryo-fetal development toxicity testing (Marie-Noëlle Blaude, WIV-ISP). The afternoon chaired by Eric Van Miert (Solvay), was devoted to alternatives for animal testing using whole embryo cultures (Geneviève Van Maele, UCL), zebrafish (Hilda Witters, VITO) and embryonal stem cells (Jochem Luisse, Wageningen University). The participants were then split in working groups for a practical exercise chaired by Graham Bailey (Janssen Pharmaceutica). Two study cases were presented after which working groups analysed the results, discussed at the closure of the course. The feedback was positive to very positive for as well the structure as the content of course. The case studies part of the course was very much appreciated and helped the participants to analyse the results and to come to conclusion.