The third and last part of the Bourne trilogy (duh), is lacking a bit in the story department, but covers it with extensive action scenes! Twi in particular take up quite some of the running time and make this movie better.
The director and star (Damon) themselves agreed that it was difficult to find a story for the last part, because the end of the second movie was quite ... advanced story-wise. How they got around that? The action scenes, for once, but they did another thing too, which I can't reveal, because that would be a spoiler. But if you watch the movie, than you'll notice it! Funnily enough I read, that this adaptation of the Bourne books is the least accurate of all three films .. if that means anything to you :o)