Dr. Zimmerman has done a fantastic job bridging a gap in knowledge about taharat hamishpacha (Jewish marital laws). This book does a great job of giving you a rundown of the basic principles and laws behind taharat hamishpacha. There is a lot of very practical information and just as importantly, this is not a sickly sweet propoganda piece touting the mystical nature of this mitzvah. Essentially, it is the modern woman's guide to taharat hamishpacha. Zimmerman offers solutions but encourages direct Rabbinic involvement if questions or problems emerge.
There is great women's health information that other books ignore entirely. Zimmerman also provides information on contraception and infertility and how those can affect mikvah practices.