A theoretical description of the effects of size, size distribution, and shape of large unilamellar vesicles on static (SLS) and dynamic (DLS) light scattering measurements is presented. Practical limitations and the relative accuracy of different analysis techniques, such as cumulants, discrete Laplace inversions, and the small-angle approximation, are investigated. It is shown that neither SLS nor DLS information can independently yield a unique size and shape characterization of a vesicle system. However, combined analysis of SLS and DLS measurements, when jointly made on the same sample, can lead to a unique determination of vesicle shape, size, and size distribution.