Štefan Zajac has completed his doctoral thesis CSc. at the Faculty of Mathematics and Physics of the Charles University in Prague in 1976. As Associate Professor he is lecturing Solid State Theory. His specialization is theoretical research in Magnetism of Solids. He published more than 50 papers in reputed journals and presented results at many conferences. He has been serving as an editorial board member of the national journal Advances of Mathematics, Physics and Astronomy. In 1993 – 1996 and 2002 – 2010 he was the President of the Union of Czech Mathematicians and Physicists.