With the new gas discoveries in East Africa and in the Levantine Basin comes the need to better understand the gas value chain and how to structure complex and capital intensive Liquefied Natural Gas (LNG) projects for the benefit of the country. Having a fiscal model is key to enable this understanding, enabling the government to assess the impact of negotiated fiscal terms on the returns to the investor and the revenues to the government. Thomas Mitro of the University of Houston and the Columbia Center on Sustainable Investment at Columbia University (CCSI) have built the first open fiscal LNG model that allows users to test different LNG commercial structures, compare domestic gas use options and assess the impact of various fiscal tools along the gas value chain. This manual has been developed to explain some concepts of the LNG value chain and how these can be tested in the model. It is available to download on CCSI’s website.