The invention describes a process for the preparation of novel surfactant alcohols and surfactant alcohol ethers by derivatization of olefins having from about 10 to 20 carbon atoms or of mixtures of such olefins to give alkanols, and optional subsequent alkoxylation, which comprisessubjecting a C.sub.4-olefin mixture to metathesis, dimerizing the resulting olefins, and then derivatizing them to give surfactant alcohols, and optionally alkoxylating said alcohols.The olefin mixture obtained in the dimerization has a high proportion of branched components and less than 10% by weight of compounds which contain a vinylidene group.invention further describes the use of the surfactant alcohols and surfactant alcohol ethers to give surfactants by glycosylation or polyglycosylation, sulfation or phosphation.