A review.This article discusses about Wurster process which is used commercialiy for coating particles from less than 100 nm to tablets, and for layering to produce core materials.The Wurster process is used com. for coating and layering.Substrates include particles smaller than 100μ, crystals, granules, pellets, and tablets.The films may be applied using water-based solutions, aqueous dispersions, or organic solvents.It is also possible to apply coatings via hot-melt, but the use of the Wurster system for this technique may be related more to the particle size of the substrate than the coating process itself.The working capacity for a Wurster insert of a particular size is generally defined as the volume outside of the partition, with the partition at rest on the orifice plate.Avoiding loading of product inside the partition helps to ensure that the nozzle remains clear at the beginning of the process.Irresp. of the amount of substrate in the Wurster insert, the fluidization pattern is controlled by the orifice plate configuration, the partition height, and the fluidization air volumeEvaporation rate or drying capacity is controlled by fluidization air volume, temperature, and its absolute humidity (dew point).The temperature of the fluidization air is generally adjusted to maintain a constant product temperatureThe product temperature, in turn, is influenced by spray rate, and humidity of the incoming air.