I once inadvertently kept the first author waiting a few extra mins. when we were going out to lunch, because my pickup basketball game ran long. He was very gracious about it, but it's not just for that reason that I say this is a good book. The all-purpose adage "moderation in all things" applies to interpersonal dependency as well. I think the authors are correct that dependency has gotten a bad rap as entirely reflecting helplessness and lack of self-reliance. They underscore the downside of excessive dependency but also the downside of detachment from others. Being able to seek and give help and support without being helpless is their touchstone.
they apply this idea to work, friendships, love relationships, aging and caregiver stress, etc. Bornstein has done a lot of the best research on dependent personality, and the book reflects these studies as well as engaging clinical cases.
If you're not specifically interested in working on a problem of being too dependent or too detached, some of the lists/definitions/guidelines may be skimmable, but even if you're just reading for information value rather than self-help the overall perspective is valuable and the cases highly readable.