We make our decisions ourselves and freely. Or do we? For our understanding of humanity, few things are as significant as the experience of having control over oneself. But what do philosophy and science say about this? Long before the discussion of free will in brain research, this problem was already recognized. Stephan Schleim uses the lecture of the prominent physicist and Nobel laureate Max Planck from the 1930s as a starting point to shed new light on the topic. The focus is on how our actual decisions in everyday situations are influenced. This distinguishes the non-fiction book from other publications that only address laboratory experiments with limited relevance. The author explains the problem from the perspectives of psychology, neuroscience, philosophy, legal studies, and physics. In the beginning, foundational concepts are introduced: What is the discussion of determinism/indeterminism about? What concepts of free will exist in philosophy? How are decisions studied in psychology? After analyzing the relevant research, Stephan Schleim, Associate Professor of Theoretical Psychology, discusses the practical dimension of the problem. How and why do we hold people accountable for their decisions? How do criminal law and morality function? And above all: How are we unconsciously influenced, and what options do we have to deal with it?.