This thesis deals with the testing extension for the Scrum methodology. The main goal of this work is to design a methodology called Scrum testing and to verify its applicability in the real project. First of all in this work is described Scrum methodology and its basic principles, roles, ceremonies and artifacts. In the next chapter the Scrum testing methodology is designed which mainly focus on testing strategies, activities, artifacts and roles. The following part of the thesis deals with the selection of research area within the Scrum testing methodology and choosing the appropriate verification method which is action research. The subject of the verification are system testing strategies that have major impact on the Scrum team functio...