In this thesis, the principles to design and implement software application to fully automate the Plug and Abandonment operations is discussed. The application is planned to be developed to enter the data manually from new wells that have not been registered yet and/or upload from the open data source of The Norwegian Petroleum Directorate for the existing wells. In this stage, the application has not been developed, thus this thesis gives premises to develop the application based on fundamental principles of Plug and Abandonment Operations under NORSOK standards.Main purpose is to achieve cost-effective and time-efficient generation of P&A report that is fully acceptable by NORSOK standards to implement in the industry. The report itself can be divided into two sections: Fundamental principles of P&A operations which is covered in the first section which includes operational phases and design premises of the application which includes GUI and database structure, software architecture and operational commands. The focus has been mainly on establishing core functionalities as the application is still in the concept phase with great potential. As well as providing the detailed concept, challenges through implementation have been considered, future work has been suggested for further development. The application will serve as state-of-the-art software application for P&A operations once it is fully completed and developed.