Vapor Sorption Analysis is a technique in which a sample is subjected to varying conditions of humidity and temperature, and the response of the sample is measured gravimetrically. Understanding the effects of water content on structure and properties is critical in the development, processing and end use of a broad spectrum of materials. The introduction of DVS fundamentally changed the field of gravimetric moisture sorption measurement, bringing outdated, time and labor intensive desiccator use into the modern world of cutting-edge instrumentation and overnight vapor sorption isotherms. DVS is a valued tool in laboratories all over the world from polymorphism and compound stability studies to bulk and surface adsorption effects of water and organic vapors.