Described herein are embolic assemblies that can be reinforced in situ. In particular, assemblies are described comprising (i) an implantable device designed to allow injection of a liquid agent through the lumen of the device or a lumen defined by the device and (ii) an implantable device and a liquid agent, wherein the liquid agent is capable of solvating polymeric material of the device. Methods of making and using these assemblies are also provided.