The present review article describes the work done on microencapsulation of water-soluble drugs using biodegradable lipophilic polymers. The manufacturing processes applied are classified into six categories : solvent evaporation or extraction, phase separation, spray drying, fluidized-bed and hot-melt methods. The processes are critically discussed. The advantages and limitations of each technique are evaluated in term of feasibility, reproducibility, yield, cost and toxicity. The authors try to explain the interactions between the physicochemical properties of drugs and polymers used, the microencapsulation technology applied and the performances of microparticles produced (microcapsules, microspheres). Finally, this work offers a better understanding on the reasons why only three of these techniques are presently used at the industrial scale for manufacturing biodegradable microparticles.