What are the reporting lines when using SCRUM methodology as compared to a "tranditional" matrix organisation where developers report to development managers, project managers and any other stakeholder at the time?
The point of Agile is to eliminate all the "reporting lines" and pare things down to the essential relationships and nothing more.
See http://www.agileactivist.com/articles/Chapter2%28v0.04%29.pdf
Scrum teams are intended to be self-organizing, not have organization imposed on them.
Read these two blog posts
http://www.practiceagile.com/2009/07/scrum-team-organization-feature-teams.html
http://www.practiceagile.com/2009/07/scrum-team-organization-feature-teams%5F28.html
That should help.
Developers report to their scrum master during daily (scrum) meetings. Scrum masters report to the product owner, but keep in mind that scrum is about being people and not machines, and thus, the whole organization structure becomes wide instead of a big triangle of people whose only purpose is to report to their superiors.
The burn-down chart is an excellent tool for reporting. And the team does not need to report anything. Like it has been mentioned, the scrum master talks to the product owner, and the burn-down chart IS the reporting tool the product owner has to look at if he has that need. Otherwise it is common to demo the product to the customer between the sprints, and that should be sufficient "reporting".
The team SHOULD ALWAYS take action if something is going SERIOUSLY wrong, and that means involving the product owner, to discuss actions that are needed.
The reporting lines within a Scrum project are dependent on the situation. At a high level the reporting lines for the project might look like this . . .
Team member => Team => Product Owner => Customers/Sponsors.
The team members are accountable to each other, and as such at the very least use the daily standup to bring their team mates up to speed with any issues and problems. Between them they will decide on course corrections, or a plan of action to fix the issue. The ScrumMaster is part of the team, and may decide to take on tasks to facilitate the removal of any impediments that the team runs into, but that does not mean that the team reports to the ScrumMaster.
The team also makes a commitment to the Product Owner (PO) when they agree on the goal and deliverable for the sprints. As such they will allow the PO to provide leadership for the project and let them (the PO) resolve any issues with respect to the clarification, scope of features.
The PO was the original champion for the project and managed to get funding and buy-in from customers and sponsors. As such the PO needs to keep those stakeholders appraised of the projects progress against the plan for delivery and success. The PO needs to ensure that the stakeholders remain satisfied and in the case that something unforseen occurs, confirm that the new plan still meets with the stakeholders buy-in.
My final note is that managers and project managers are still involved, though more indirectly to help the team remove and solve their impediments that are inhibitors to their success.
I don’t believe it is the intention of Scrum to define any reporting lines whatsoever, at least not in the formal context. It’s a software development methodology, not an organisational structure approach. Although I often play the role of a Scrum Master and my direct reports do the development, we could conceivably operate with one of the other guys playing the lead role and myself being a developer without it being contrary to the formal construct. Of course this could be interesting in the event of a dispute but for the most part I think Scrum and reporting lines are two independent concepts.