A systematic procedure that helps develop gas-solid and gas-liquid-solid catalytic fluidized-bed reactors has two components - screening and scale-up. In screening, a reactor type is selected first from the variety of multiphase reactors. If fluidized-bed reactors are chosen, further screening is carried out using experimentally verified models to account for the detailed hydrodynamic features of the reactor. Decisions are made on the fluidization regime, heat management scheme, solid recirculation, use of reactor internals, and so on. In addition, heuristics are presented to anticipate and address issues such as catalyst agglomeration, breakage and deactivation, and changes in the nature of fluidization over the long term. The second component provides criteria to directly, scale tip the bench reactor to the production reactor, while maintaining a selected reactor performance index such as conversion, product yield, and selectivity.