The invention describes a process for the preparation of surfactant alcohols and surfactant alcohol ethers which are, inter alia, highly suitable as surfactants or for the preparation of surfactants. The process, starting from olefin mixtures having a defined minimum content of linear hexenes, gives mixtures having a predominant fraction of branched dodecenes, which are subsequently derivatized to give surfactant alcohols and then optionally alkoxylated.The surfactant alcohol mixture obtained in the process has a degree of branching of from 2.0 to 3.0 and in particular exhibits advantageous properties as regards ecotoxicity and biodegradability.A description is also given of the use of the surfactant alcohols and surfactant alcohol ethers as surfactants by glycosidation or polyglycosidation, sulfation or phosphation.