Water-in-oil AOT microemulsions were studied in the presence of a hydrophilic polymer (poly(oxy)ethylene, PEG) using dynamic and static light scattering techniques. Different polymer molecular weights (3000, 35 000, and 300 000 Da) and water contents were used. The formation of polymer-induced clusters was found to be strongly dependent on the polymer and water pool sizes. While small polymers encapsulate completely inside the reversed micelles, large polymers do not fit inside and form clusters. When the size of the reversed micelles is varied by changing the water content, a rather sharp transition occurs between polymer-induced clusters at low water content, and reversed micelles with encapsulated polymer at high water content.