Flow reactors offer considerable advantages over batch stirred tanks for reactions involving high temperatures and pressures or where temperature and residence time control are critical to performance.  This talk presents a condensation reaction that took several hours in a batch stirred tank but can be executed in a matter of minutes in flow (using AMaR-4P reactors); with similar yields. An economic analysis from a CAPEX and OPEX point of view is also presented to showcase the great advantage of operating in flow.