The study of forward osmosis (FO) membranes is increasing in importance due to their well-known advantages (low-energy consumption and reduced fouling) when compared to high-energy consuming membrane technologies such as reverse osmosis (RO). This research focused on the characterization of the natural organic matter (NOM) fraction causing fouling on the active layer of a FO membrane in a plate and frame FO membrane configuration, when using secondary wastewater effluent as feed water, and seawater as draw solution (DS). The study also investigated fouling control and cleaning approaches.