Introduction. Basics: Roots of Performance Analysis -- Definitions and concepts -- Performance analysis in game sports. Observational systems: Assessment of behaviour -- Elements of observational systems -- Validation of observational accuracy -- Typical data analyses. Tracking systems: Functioning of different technologies -- Validation of accuracy -- Typical data analyses. Theoretical performance analysis: Stochastic approaches -- Dynamical systems approaches -- Advanced modelling. Practical performance analysis: Aims and problems -- Qualitative game analysis -- Integration of game analyses into training -- Game analysts in professional training systems. Outlook: Technological developments -- The future of training systems.