As a technique for thermal analysis, calorimetry has a broad spectrum of applications which are not only restricted to studying the thermal characterization (e.g. melting temperature, denaturation temperature and enthalpy change) of small and large drug molecules, but are also extended to characterization of fuel, metals and oils. Differential Scanning Calorimetry is applied to study the thermal behaviors of drug molecules and excipients by calculating the differential heat flow required to maintain the temperature difference between the sample and reference cells. Microcalorimetry is applied to study the thermal transition and folding of biological macromolecules in dilute solutions and could also be applied in formulation and stabilization of therapeutic proteins. This book consists of research from around the world on the usage of calorimetry which is grouped under three sections; namely, Thermal Analysis of Phase Transitions of Polymers and Paraffinic Wax, Indirect Calorimetry to Measure Energy Expenditure, and Applications of Calorimetry into Propellants, Alloys, Mixed Oxides and Lipids.