This proposal continues our investigations into polyelectrolyte-surfactant thin films which form at the air-solution interface. Our previous work investigated structure development in films of polyethyleneimine and cationic alkyltrimethylammonium bromide (CnTAB) surfactants, as well as encapsulation of hydrophobic species within the films. Here we propose to investigate control of the film mesostructures by altering the curvature of the surfactant micelles. We will use a surfactant with a larger headgroup to increase curvature and mixed micelles of C16TAB with a double chain surfactant, to decrease curvature. Structures composed of spherical micelles may be more efficient at encapsulation of hydrophobic species than the 2D hexagonal films, and incorporation of DODMAB vesicles into the membranes raises the possibility of trapping water soluble species in the vesicle interiors.