Methods for supplying one or more vapors, under reduced pressure, to an environment are provided. The vapor may comprise at least one polymerizable component. In some cases, at least two components may be combined to form the vapor. The components may be provided as separate vapor streams, which may be combined and homogenized. Methods of the invention may also be useful in the deposition of materials on the surface of a substrate. In some cases, the material may form a layer, such as a polymer layer, on the surface of a substrate. The present invention may be useful in applications that require the formation of homogeneous films on the surface of a substrate.