Twin-Screw Granulation (TSG) has emerged as a popular continuous manufacturing technology for consistent, repeatable high-quality production of both standard and complex dosage forms. This application note presents parts of a wide-ranging experimental plan involving the building of a data-driven process map for twin-screw granulation using real-time particle size measurement. The experiments presented here demonstrate both how PAT can dramatically decrease the time required to define, execute and analyse the data from a DoE, and how it can provide information which is not plausible from traditional off-line analysis methods.