Where are the boundaries of musical improvisation? What are the areas of freedom? What relationships among musicians determine free interplay? How indeterminate can a composition be during performance while still being composed? For 45 years, Vinko Globokar has been developing compositional strategies with an element of indeterminacy. In these compositions, interpretative freedoms are integrated into a composed work. Sabine Beck places the diversity of Vinko Globokar at the forefront. The relationship between improvisation and composition is explored, along with all its shades of indeterminacy. It is a scholarly endeavor to understand a fleeting field and its determinants, placing Globokar in the context of his contemporaries and companions (Stockhausen, Berio, Kagel). It provides a comprehensive view of his musical oeuvre, including analytical considerations.