NTS under MDGM is a voluntary, non-governmental, politically unrelated, non-profit creative and professional association. More than 1,500 scientists, engineers, technicians and other mining, geology and metallurgy specialists, as well as legal entities from the country and abroad, are associated with this activity. The Union is an association for private benefit and acts in favour of its members. NTS is a regular member of the Federation of Scientific and Technical Unions in Bulgaria and since 2003 has started the replacement of the membership cards with new federal alliances. 

There are 14 regional organizations, 34 scientific and technical societies and clubs and 6 integrated units. The collective members of the Union are currently 25.