Abstract: A vapor collection method and apparatus capable of capturing vapor compositions without substantial dilution. The method and apparatus utilize a material that has a surface with an adjacent gas phase. A chamber is positioned in close proximity to a surface of the material. The position of the chamber creates a relatively small gap between the surface of the material and the chamber. The adjacent gas phase between the chamber and the surface define a region possessing an amount of mass. At least a portion of the mass is drawn through the region by induced flow. The utilization of a small gap limits the flow of mass that is external to the chamber from being swept through the chamber by induced flow.