Summarising the thesis, we observe the big picture. Causality for labs obeying general probabilistic theories and for labs obeying quantum mechanics. For the n-lab case we introduce the concept of dynamical causal order. We develop mathematical tools to witness causally non-separable quantum processes and to study causal polytopes. We rule out a causal model for a Bell experiment and develop the first quantum causal discovery algorithm for the discovery of quantum causal models.