While structurally, the hydration state of lipid-rich and polymer-rich GUV membranes are comparable, this does not inform us about the dynamics within these different membrane compositions. We therefore investigate hybrid membrane dynamics using fluorescence recovery after photobleaching (FRAP). The DiO lipid probe and the PBd22-PEO14-TMR polymer probe were used to independently study the mobility of lipid-like and polymer-like molecules in these membrane environments, respectively. The diffusion coefficients shown in Figure were extrapolated from the fluorescence recovery curves of a bleached area in the upper pole of a vesicle. The fluorescence recovery curves were fitted using modified Bessel functions with a single recovery time. Attempts to fit the recovery data with two recovery times did not improve the fits, indicating that the probes diffuse through homogeneous membrane environment, which is supported by our measurements of hybrid membrane mixing and hydration state that we have already presented.