First visit of laboratory experts in Nis, Serbia was carried out in the period 17-19 December 2013 under project activity 12 “Exchange of good laboratory practices”. Bulgarian experience will be transferred by conduction of two visits of BG lab experts. During the first visit the discussion was focused on the observation of the existing procedures, rules and practices in RS labs. Bulgarian experts provided information regarding secure of ISO procedures in BG and especially in terms of referent labs. Recommendations on the improvement and unification of the procedures was provided. Second session will be focused on consolidation of practical procedures with regard to the new supplied equipment and further application to become referent lab (compliance with ISO 17025).