Accreditation Body of Serbia (ATS) an year before began intensive activities to extend the scope of the accreditation of providers of proficiency testing (PT providers) according to SRPS ISO/IEC 17043:2011. Meanwhile, in late 2012, the accreditation of PT providers by the decision of EA General Assembly becomes part of the EA MLA Agreement. Accordingly a number of activities were undertaken: from formation of management system documentation, training of assessors to gain practical experience in the assessment of other accreditation bodies (ESYD - Greece Accreditation Body).