A desalination process for the production of potable water comprising the steps of extracting at least one distillate stream 150 from at least one higher temperature stage 109 of a Multistage flash distillation (MSF) separation process 100 and supplying said at least one distillate stream to at least one stage of a separation process 200 operating at a lower temperature than said higher temperature so as to maximise the use of sensible heat in said distillate stream by heat transfer in said at least one stage, to lower the external heat input of said at least one stage and of the process overall. The distillate stream is used to provide additional heat exchange to a multiple effect distillation (MED) process 200, a reverse osmosis system (not shown) or to preheat the feed stream of the MSF process.