Abstract: The invention relates to a process for preparing immunogenic complexes in which an amphiphatic antigenic protein or peptide in dissolved or solubilized form is contacted with a solution containing a detergent, a sterol, and a glycoside comprising hydrophobic and hydrophilic regions, in at least the critical micelle forming concentration, the detergent is removed, and the immunogenic complex formed is purified. Optionally, the solution with which the antigenic protein or peptide is contacted also contains a phospholipid, preferably phosphatidylethanolamine. The preferred sterol is cholesterol, and preferred glycosides are saponins, espeically Quil A.The immunogenic complex is useful as a vaccine. Its immunogenic power is higher than that of corresponding micelles formed by aggregation of the antigens, and is also higher than that of the antigens incorporated in liposomes.