Natural gas as an important energy resource remains a key factor regarding reliable energy supply, even in times of decarbonization. With the increasing relevance of the resource, natural gas trading has steadily evolved. In comparison to international crude oil trade, however, contractual peculiarities and a different structure distinguish the international natural gas trade. ComFin Software GmbH develops and distributes a Commodity Trading and Risk Management Software with a focus on crude oil trading. Within their effort to expand the reach of their product, the company has decided to develop a module for natural gas trading. This thesis should lay the groundwork for further development of the software module. In order to provide ComFin Software GmbH with a general insight into natural gas trading, the topic will be thoroughly analysed in the following thesis within the framework of an extensive literature research. The development of the market will be highlighted and gas sales agreements as well as the most important contractual provisions will be analysed in detail. On that basis, suggestions for necessary adaptations of the module will be provided. A software requirement analysis, which uses the previously gathered knowledge and the basic architecture of the current software module, will be conducted to deliver the needed adaption steps. The software requirement analysis has shown that particularly changes in the area of input of contract quantities and qualities are necessary. Furthermore, the system shall be able to depict the stated gas pricing formulas. Other adaption steps include the integration of contractual peculiarities and certain norms. Through the proposed changes, the system will be able reflect the contractual characteristics of natural gas trade.