Metoprolol tartrate (MT) was encapsulated with Eudragit RS^® by an emulsion-solvent evaporation method to develop a controlled release dosage form. This process was efficient, reproducible and not time consuming. Different release characteristics were obtained by changing the drug to polymer ratio and varying the percentage of aluminum tristearate incorporated in the encapsulation medium as a smoothing agent. In the presence of aluminum tristearate, the formed microcapsules were typically spherical and exhibited size distribution within a narrow range. High drug-to-polymer ratio resulted in increased microcapsule size and drug release rate. The microcapsules showed pH-independent dissolution behaviour.