Alexander Koblenz, the long-time coach and confidant of Michail Tal (World Champion 1960-61), presents in this book a chess course in 16 lessons that he conducted in Riga at the time. He thematically focuses on middlegame strategy and tactics, as well as selected endgame questions, which are explained through games and game fragments. The course includes twelve practice units, each with six tasks that are not linked to any specific requirements and can be mastered independently by the reader; the corresponding solutions are provided at the end of each practice section. Koblenz's original work (first German edition 1967) was later supplemented with examples from more recent practice and an interview that Koblenz gave in 1990. An additional concluding chapter on the limits of human performance is also included.