A novel design of a multi-staged, continuous flow spouted bed, suitable for counter-current, crosscurrent, and fed-batch gas-solid contacting is developed. Single and three-stage conter-flow units are studied, the residence time distributions (RTD's) of the solids therein are measured and two compartmental models are developed to fit this family of RTD's. The first (two-parameter) model is satisfactory for the single stage units, and three-stage units at high gas flow rates. The second (three-parameter) model describes each stage as two CSTVs in parallel with a PFV in series. It provides better agreement with experimental data in the three-stage case.