Video and digital image analysis were used to understand the limiting steps in a submerged jet microencapsulation process for mammalian cells. Hydroxyethylmethacrylate-methylmethacryl copolymer (HEMA-MMA) two phase droplets with an aqueous core are formed by coextrusion at a needle tip and fall through a layer of hexadecane prior to precipitation in an aqueous medium. Initial eccentricity was lowest when the capsule cores contained 20% (w/v) Ficoll and the inner needle protruded 100 mu m past the outer needle. Capsule morphology was refined in the hexadecane overlayer, and was strongly affected by crossing the hexadecane-precipitation bath interface.