A gas-to-liquids process and plant for treating natural gas, in which the natural gas is subjected to expansion through a flow restrictor so as to undergo cooling through the Joule Thomson effect, enables liquids to be separated from the gas stream. The natural gas may be cooled before it reaches the flow restrictor by heat exchange with fluid that has passed through the flow restrictor. This decreases the proportion of longer-chain hydrocarbons in the natural gas, which may simplify subsequent processing, and may enable the size of the plant to be decreased.