The Product Owner is responsible for what is being developed and in what order. The Scrum Master supports the team in developing their own process based on the broader framework of Scrum. The development team determines how to achieve what the Product Owner wants.
If you are a manager, don’t be surprised that “manager” is not mentioned as a role. Managers still have an important role in all companies that work with Scrum. The Scrum Framework only defines the roles that are specific to Scrum and not all that can and should exist in companies where Scrum is applied.
The Product Owner is the central point in the product strategy. He may decide which features and functions are to be created and in what order. The Product Owner has the task of communicating a clear vision of what the Scrum team wants to achieve to everyone involved. Therefore he is ultimately responsible for the successful development and implementation of a solution.
Whether the focus is on an external product or an internal application, the Product Owner is committed to ensuring that the best possible work can be done at all times. This can also include work with a technical focus, e.g. revision of the data model to optimize performance. In order to ensure that the team achieves what the Product Owner wants as quickly as possible, the Product Owner must actively work with the Scrum Master and the development team and be available for quick answers to frequently asked questions.
The Scrum Master helps all participants to understand and internalize the values, principles and methods of Scrum. He acts as a coach, taking the lead in the process and helping the Scrum team and the rest of the company to develop a powerful Scrum strategy that is tailored to your company. The Scrum Master also helps the company through the difficult change management process that can occur during the introduction phase of Scrum.
The Scrum Master also acts as a mediator and can thus solve problems within the team and improve its implementation of Scrum. He is also responsible to protect the team against external influences and to remove obstacles that can affect the team’s productivity (if the people concerned cannot solve these problems themselves). However, the Scrum Master is not allowed to exercise control over the team, so this role is not identical to that of a traditional project or development manager. The function of a Scrum Master is that of a leader, not a manager.
In traditional approaches to software development, there are many different types of jobs, such as software architects, programmers, testers, database administrators and designers. In Scrum only the role of a development team is defined, a diverse and cross-functional group that unites exactly those people who are responsible for the design, development and testing of the desired product.
The development team organizes itself in order to be able to optimally work towards the goal set by the product owner. The development team typically consists of three to nine people and the members of the team must combine all the skills and knowledge needed to produce high quality and working software. Of course Scrum can also be used for development work where larger teams are required. Instead of a large Scrum team with 35 people, however, you should rather aim for several small Scrum teams with one development team each, consisting of a maximum of nine people.