When a project is big enough to have two or more teams working on the same project, we recommend that each team have its own backlog of User Stories and each team size its own stories with Story Points. Of course, this inevitably raises the idea of having each team conform to some “story point standard” so that project progress and team progress can be tracked "uniformly." Doing this more or less means that teams have to normalize story points across all the teams so that, for example, a 5-point story for one team is the same as a 5-point story for every other team on the project; an 8-point story is the same for every team, etc., etc., etc.
All I have to say to this idea is: “Ugggghhh… What a collosal waste of time!" I’ve seen teams try to do this and the effort put into trying to ensure uniformity of sizings across multiple teams is enormous.
I’m happy to report that there’s an easier way that still allows for overall project progress to be easily seen as well as individual team progress. In essence, instead of normalizing based on story points we suggest “normalizing” based on the calendar. Let me explain: let’s assume, for example, there are two teams on a project, each having its own backlog that has been sized with story points. Team A has 2000 story points on its backlog and Team B has 500. In this case you would have three burndown charts to track progress: one that’s combined (showing 2500 total points), a second one for just Team A (showing 2000 total points), and a third one for just Team B (showing just 500 points). In order to determine relative progress for Team A and Team B, you base it on the number of points completed vs. the number of iterations... Thus, if you're half-way through the project (e.g., 5 of 10 planned iterations are complete), you would expect Team A to be ~1000 points complete (50% of its total) and Team B to be ~250 points complete (50% of its total).
Where things get to be a little more complicated is when you have numerous teams working on a project (for some enterprise application projects we’ve worked with, we’ve seen over 40 teams working on the same project). With two teams, it’s fairly easy to bounce back and forth between Team A’s release burndown chart and Team B’s release burndown chart. When you have more than that, you can create a very simple chart (using any spreadsheet tool) that shows “percent calendar complete” and “percent story points complete” for each team. Following are two examples that we’ve used (they show the same data, just in different formats):
You’ll notice in the first chart that the schedule is 60% complete (the black bars) and then each team’s relative progress is shown. In the second chart, a stacked bar is used to show overall te am progress. In this made-up example, Team 1 is slightly ahead, Team 5 is slightly behind, and the other teams are perhaps struggling...
I’m sure you can think of other, different ways of showing the data, so do whatever’s most helpful. The key is that this approach is so much easier and simpler than trying to normalize the sizing of story points across multiple teams.