This book is a very opaque and general review of depression, diagnosis, and treatment options. It heavily advises medical intervention, counseling, and/or advanced therapeutic remedies. The advice is very basic; anyone in particular could provide it if you asked the pertinent questions.
In my tenured experience of counseling, both religious and practical, depression is most often the reaction to phenomenological events and life experiences that damage the person's perceptions of themselves. If they have a terrible life, the first course should perhaps be to attempt to improve it. Medical intervention may be required if they have a wonderful life with no reason to be downtrodden. In my opinion, we should exercise more caution towards our approach to medication.
I recommend this book for those with little knowledge of psychology who need basic information to help them on their way.