Relationships: How to Make Bad Relationships Better and Good Relationships Great is a book that is unsurprisingly about relationships. It is a very general book about relationships though, so how much you get out of it may depend on where you are in terms of being able to develop and maintain relationships. Another thing to note is that both of the authors are Christians, and while they keep the religious parts rather low-key it is there and is worth being up front about since the title doesn't inform the reader about this.
I found the book to be full of good insights and general advice. It starts out with talking about the need to know yourself and understand how your family upbringing has affected who you are and how you react to things. It then talks about friendships and eventually moves into romantic relationships, sexuality, and even how to deal with breakups. It then ends with a somewhat tacked on feeling chapter on having a relationship with God. It does have some good insights as well, but felt a bit different than the rest of the book.
That said the book mainly deals with forming new relationships or dealing with certain aspects of relationships like sexuality or breaking up. It doesn't really talk about what to do with strong established friendships, or more serious relationships like long term dating relationships or marriage. This makes me think that this is a book geared towards a younger audience of like late teens to early twenties. I could be wrong on that, but with the absence of a chapter on marriage it really felt like that was a big relationship to miss in the spectrum.
Also while I did enjoy the insights of the book, the chapters are pretty easy to get through and with the wide amount of relationships they hit on it all feels very introductory. There have been books written about what they try to cover in a chapter or two. It's well done, but you may find yourself wanting to go a little deeper on certain subjects that the Parrotts just weren't able to do.
So yeah, Relationships is a good general book on relationships, but if you're hoping for it to cover a specific area in depth you're probably going to be slightly disappointed. You'll also be out of luck if you're looking for a lot of insight on marriage and how to build a successful marriage. Due to this it feels like a book that will have a limited impact and a limited audience, but it's good for what it is.