Cover picture: Two-photon excitation fluorescence intensity images (false color representation) of GUVs formed of DLPC/DPPC (A), DLPC/DSPC (B) and DLPC/DAPC (C) 1:1 mol/mol, labeled with N-Rh-DPPE. The images have been taken at the top part of the GUV at temperatures corresponding to the fluid phase [top images in A (42.0°C), B (49.5°C) and C (66.5°C)] and the fluid-solid phase coexistence [bottom images in A (26.4°C), B (34.0°C) and C (42.5°C)]. The non-fluorescent areas in the images correspond to solid phase phospholipid domains. Note the different solid domain shapes as the hydrophobic mismatch in the binary mixture increases. The non-fluorescent areas in the GUV span lipid bilayer showing coupling between the inner and outer leaflet of the membrane. The mean diameter of the giant unilamellar vesicles (GUVs) was around 30 µm. See the article by Bagatolli and Gratton on p. 434.