The molecular architectures of enveloped viruses provide a demonstrative example of perfectly arranged macromolecular complexes, which are formed via highly specific interactions of all structural components. Virus morphogenesis is a multistep process that depends on the concerted actions of many viral and cell components, as well as a fitted organization of main viral constituents. The virus envelope is composed of a mixture of lipid raft and nonraft domains. The domains are recruited from the host cell membrane as discrete well-ordered lipid-protein units during virus assembly. The raft-like nature of the influenza virus A envelope was visualized using a novel approach of cold solubilization of detergent-resistant membranes from intact influenza virus A virions with a mixture of NP40 and octyl glucopyranoside, two nonionic detergents drastically differing in their raft-solubilizing activities. The virus envelope is apparently an ensemble of flexibly joint platforms, which are composed of surface glycoproteins (hemagglutinin and neuraminidase), the matrix M1 protein, and lipids. The modern concept of the transmembrane asymmetry of lateral domains in biological membranes was used to explain the solubilization mechanism revealed. Based on the principles of this concept, the M1 protein shell was assumed to provide a structure-forming framework to support asymmetrical rafts in the virus envelope.