Establishing the relative stability of crystal polymorphs using computational calculations is extremely valuable in identifying those that are thermodynamically plausible. This has proven particularly useful for the development of APIs, and it is finding increasing applications outside academia . These methods, however, fail to capture the role played by components in a preceding crystal-forming fluid phase in directing phase separation towards a specific outcome. In the case of crystallization from solution, the parent liquid often has a composition radically different to the crystal itself, where solvent and other solution additives are often excluded. Even in the simplest example of a single-component molecular crystal emerging from a two-component solution-comprising the solute building blocks and solvent-varying the solute concentration can change the mechanism, rate and polymorphic outcome of precipitation. Computational material discovery/prediction methods based solely on thermodynamic assumptions, therefore, cannot identify how, or even if a thermodynamically favourable polymorph can be obtained by crystallization from solution.