Unsaturated alcohols are prepared by selective hydrogenation of unsaturated aldehydes, ketones, acids, and their esters. Special attention is paid to the Ru-Sn catalytic systems suitable for such reactions. The Ru-Sn catalyst is usually prepared by co-impregnation, sol-gel method, or so called surface controlled reaction. Interesting topics and specific features regarding this catalyst system are discussed. Role of Sn and its promotion effect on Ru catalytic properties are explained in a separate chapter. These properties are documented on several practical examples (e.g., selective hydrogenation of cinnamaldehyde, crotonaldehyde, oleic acid, etc.).