This chapter contains section titled: Anhydro Derivatives of Mevalonic Acid as Possible Intermediates Liver Enzyme System and its Cofactors in the Synthesis of Squalene and Cholesterol from Mevalonic Acid Activation of Liver Enzyme System by Reducing Agents and the Rôle of SH-Component in the Synthesis of Squalene Rôle of Magnesium and Manganese Ions Enzymic Formation of Derivatives of Mevalonate Formation of Higher Acids from Mevalonate References Discussion