A Scrum Master is a member of a Scrum Team which is a team that is practicing a particular type of Agile Software Development Methodology referred to as "Scrum." Though a lot of the traits found in a Scrum Master are similar to what you might find in a project manager, there are some differences.

A Scrum Team is comprised of developers, testers, a product owner and a Scrum Master. The Scrum Master maintains the processes of the team, so in this way is similar to a project manager in a traditional environment. The Scrum Master facilitates the meetings of the Scrum team and helps the team reach consensus. However, unlike the project manager in traditional environments, the Scrum Master is not considered the lead and is not held accountable for the final outcome of the team. The team is responsible as a whole and the Scrum Master does not bear additional responsibility.

The Scrum Master's role is to remove any impediments hindering the team from meeting their sprint goals. The Scrum Master ensures the agreed-upon rules of the team are followed and keeps the team focused on the tasks on hand.

Scrum and other agile methodologies are focused on collaboration with the business and work iteratively in order to allow for changes to requirements. For this reason, the project management style is considered more "adaptive."