I am a drama foundation student and this has been our main source for the voice classes. Different approaches work for different people - this has really worked for me for the following reasons:
there are theory sections which inspire and create a sense of excitement and adventure. These are followed by exploratory and technique-building exercises which really do work! The accompanying dvd demonstrates most exercises (only nag I have found here: a few more of the exercises would have been useful inclusions). Finally there is reference to the other great voice practitioners' work, such as Cicely Berry, Kristin Linklater and Patsy Rodenburg, accompanied by detailed reading suggestions and reference to other resources, such as online poetry sites, practitioners sites etc. The authors clearly have amassed a vast experience of various distinct disciplines in the field, including for example, Chi Kung, Alexander's and Yoga in the body work, and integrated them into their own unified approach.
The book is split into the following sections:
1. relaxation, release, alignment
2. connecting breath and voice
3. exercising the support and control system
4. resonance and range
5. work on the articulators
while the appendices include sample workouts, biblios etc
A very thorough, practical and effective approach for discovering, exploring and extending your vocal capabilities, including communication and expresiveness.
PS I am adding to this review a year later. Being near the end of my second year in drama and having amassed some theatre and film performance experience, I still use this book and am still making fresh discoveries from it. For example, the mouths exercise (resonating from different areas of the torso and head) has recently yielded some great results - I believe it might have its roots in Grotowski. An invaluable resource that you will actually keep revisiting, rather than read once and forget on the shelf (or pile)