In this contribution, the nonlinear dynamic behaviour of reactive distillation columns for the production of MTBE and TAME is studied. The focus is on steady-state multiplicity and a rigorous bifurcation analysis of pilot plant reactive distillation columns for both processes is presented. The different sources and physical causes for the existence of multiple steady-stales in MTBE and TAME synthesis are discussed. Further, a rigorous experimental verification of steady-state multiplicity in a pilot plant reactive distillation column for the production of TAME is presented. Finally, some remarks on the implications of multiple steady-states on column operation are made.