Vladimir Gribov was one of the founding fathers of high-energy elementary particle physics. This book derives from a lecture course he delivered to graduate students in the 1970s. It thus provides today's graduate students and researchers with the opportunity to learn from the teaching of one of the twentieth century's greatest physicists. Its content is still deeply relevant to modern research, for example exploring properties of the relativistic theory of hadron interactions in a domain of peripheral collisions and large distances that quantum chromodynamics has barely approached. It covers a combination of topics not treated elsewhere, whilst remaining self-contained and thus accessible at graduate level. In guiding the reader, step-by-step, from the basics of quantum mechanics and relativistic kinematics to the most challenging problems of high-energy hadron interactions with simplifying models and physical analogies, it demonstrates general methods of addressing difficult problems in theoretical physics.