The significantly lower fouling potential of the forward osmosis process compared to reverse osmosis membranes, operating under the same feed conditions, has been shown by a number of academic researchers. However more importantly under real world conditions on challenging feedwaters, Modern Water has demonstrated that on one particular site in Oman no chemical cleaning was required over several years operation, yet the conventional process required cleaning every few weeks with several membrane changes [ 10]. This of course also means a reduction in the use of membrane cleaning chemicals and improved availability.