Natural Gas: Exploration and Properties is the first volume in a series of textbooks to be continued with Natural Gas: Operations and Transport (second volume), as well as Natural Gas: Customers and Consuming Industries (third volume). This series will end with a fourth volume Natural gas: Economics and Environment. The aim of this series is to provide a student with the basic tools required when following the flow of gas from the reservoir to the burner tip. The first chapters or sections of Natural Gas: Exploration and Properties provide an overview of the market environment and the geological environment with reference to natural gas. Natural gas properties and characteristics are dealt with subsequently, while phase diagrams relating to gas reservoirs form part of an additional chapter. Geophysical and formation evaluation methods are further described in the following sections. The text ultimately ends with an introduction to the principles relating to fluid and gas flow, as well as to the formation testing of gas reservoirs.