This Conference is dedicated to process chemistry and organic synthesis (contrasting to previous PAT conferences and symposia which have been predominantly formulation focused). With an emphasis on the science and technology associated with the synthesis and manufacture of active pharmaceutical ingredients (APIs), the aim is to showcase the use of PAT as a tool for increasing process understanding, robustness, reproducibility and efficiency in API manufacture, both in development and commercial production. Regulatory and QA issues will be touched upon where appropriate.