Heterogeneous catalysis is vital to sustain humanity and to address important societal challenges such as achieving net zero. Heterogeneous catalysis is also chemically complex, and the realisation of new catalysts is challenging. Catalysts themselves can contain multiple active elements; for example, the catalyst used for the Haber-Bosch process, which is integral to feeding 50% of the global population, typically contains iron, aluminium, calcium, potassium, and oxygen, with activity subtly dependent on composition. The composition of catalytic materials can be explored successfully via data-driven approaches, yet catalytic reactions occur at the surfaces and interfaces of these materials, and therefore the material properties must be investigated also as a function of the reactive surfaces and interacting medium; furthermore, a rational design process must also consider the intricacy of reaction mechanisms to ensure appropriate reactivity and product selectivity, which includes sensitivity to temperature and pressure, to result in truly industrially relevant catalysts. The complexity of such catalytic systems quickly becomes intractable to fully explore with current experimental or computational efforts.