This was a nice account of one researcher's career studying MS. The first half of the book is especially interesting, since it goes to some extent into the mechanisms of the disease.
The second half sort of wanders off into the pharmaceutical research, which is less interesting to me. The discussions of Tysabri's introduction(as Antegren), and subsequent recall, is interesting -- especially since that's the medication I now take. The book ends before the drug's re-introduction into the market.
Overall, I very much appreciated the book because it's not written for fourth-graders, is actually about the disease (and not one person's experience with the disease), and is not so dense that I can't access it as a layperson. What I found unsatisfying, I think, is what I find unsatisfying about the disease itself. It seems that nobody (not even scientists) really understands it, or really has more than a tenuous grasp on how the CNS itself works. Which is a sobering realization.