This paper presents main theoretical results obtained in vacuum explosive-emission electronics by using of the numerical methods aimed to the direct solution of Vlasov Poisson kinetic equations. It was shown that computational physical kinetics makes it possible to explain a number of important physical laws occurring in vacuum diodes unlike widely used Particle-in-Cell or hydrodynamic simulation. The kinetic approach makes it possible to take into account nonequilibrium non-Maxwellian effects mainly associated with the “tails” of distribution functions. The advantages of kinetic simulation are shown on two highly relevant problems of vacuum electronics are considered in details.