International conference “Mathematical Optimization Theory and Operations Research” (MOTOR 2021) will be held on July 5-10, 2021, in the picturesque place not far from Irkutsk (Russia) and Lake Baikal. The conference brings together a wide research community in the fields of mathematical programming and global optimization, discrete optimization, complexity theory and combinatorial algorithms, optimal control and games, and their applications in relevant practical problems of operations research, mathematical economy, and data analysis.