Freeze-fracture and cryo-transmission electron microscopy, low-angle X-ray scattering, 31IP NMR, and Raman spectroscopy have been used to characterize the properties of synthetic tetraether bolaform amphiphiles in aqueous solution (Kim, J.-M.; Thompson, D. H. Lungmuir 1992,8, 637-644). A mixture of morphologies composed of multilamellar vesicles, quasioriented multilamellar stacks, and isolated lamellar sheets, observed by electron microscopy immediately after sonication of l,l’-Oeicosamethylene-2,2’-di-O-decyl-rac-diglycero-3,3’-diphosphate (l), l,l’-di-O-decyl-2,2’-O-eicosamethylene-3,3’- diphosphate (2), 1 ,l’-O-eicosamethylene-2-O-eicosyl-ruc-diglycero-3,2’,3’-diphosphate (3), and 1,l’-0-hexadecylmethylene- 2,2’-di-O-octyl-rac-diglycero-3,3’-diphosphate (4) in imidazole buffer, were converted to large unilamellar and multilamellar vesicles upon heating above Tc. Axially symmetric powder pattern lineshapes, consistent with a lamellar phase, were observed by 31P NMR for the hydrated lipids 1-4 below Tc; an isotropic signal also appeared above Tc or upon jumping the pH to 10.0. Small-angle X-ray scattering results indicate a lamellar spacing of 35.2 Å for dry 1 below its phase transition temperature that is reduced to 27.2 Å upon passing through Tc. Raman spectra revealed a high degree of alkyl chain ordering at room temperature which gradually decreased as the solution temperature was increased. These data support a model wherein the bolaform amphiphiles span a monolayer-type membrane with both polar headgroups residing at opposing membrane interfaces and disfavor one requiring large contributions from U-shaped bolalipid configurations within the lamellar phase. These data also suggest that the lipid molecular structure and dispersion method are both important determinants of solution morphology.