Para-xylene is produced by toluene methylation by charging toluene and a methylating agent to a fluidized bed of catalyst at a rate sufficient to maintain the fluidized bed in a turbulent sub-transport flow regime, reacting the toluene with the methylating agent, and recovering para-xylene from the fluidized bed. The fluidizable catalyst is a microporous material having a Constraint Index of about 1 to about 12. The relative concentration of the catalyst particles having a major dimension of less than 40 microns is controlled at between about 5 and 35 weight percent. The catalyst particles have an apparent particle density of about 0.9 to 1.6 grams per cubic centimeter, a size range of about 1 to 150 microns, and average particle size of about 20 to 100 microns.