Improved biocompatible liquid delivery compositions, which are useful for the formation of sustained release delivery systems for active agents, are provided. The compositions include liquid formulations of a biocompatible polymer or prepolymer in combination with a controlled release component. The controlled release component includes an active agent. These compositions may be introduced into the body of a subject in liquid form which then solidify or cure in situ to form a gelatinous controlled release implant or a film dressing. The liquid delivery compositions may also be employed ex situ to produce a gelatinous controlled release implant. Methods of forming a gelatinous controlled release implant and employing the liquid formulations in the treatment of a subject are also provided.