This reference encyclopedia is great for avid birders, students or those just getting involved in birding. It covers 9, 800 species of birds world wide. One thing I like about the book is that there are so many contributors the view is not slanted in any one way. But, at the same time it is very well organized and flows nicely.

Although this book includes species common to North America, it also mentions other species that even an avid birder may not be familiar with. A 16 page index is also included to make finding the information you are looking for much easier.

The excerpts about each family of birds are about 3 or 4 pages each and are organized alphabetically. And, although they are written by experts, it is not overly filled with jargon, completely understandable to a non-scientific audience. So, it is not as if you have to reference another book or dictionary to make sense of what they are saying. It seems to be written at a high school reading level.

The other thing I like about this book is what is called the �Facfile� tab for each family of birds. It shows a map of where these birds can be found. In addition it also has information about their habitat, mating rituals, nesting habits, diet and size. You can also quickly see whether or not they are endangered. There is also a �Special Features� Article that highlights factors that impact birds and their habitats such as pesticide usage.

Lastly, in contrast to many bird reference books, this also gives fascinating information on bird species that makes the book a pleasure to read not just pick up occasionally as a resource. For example, The New Caledonian crow creates tools to �flush out� insects and pigeons produce milk similar to mammal milk. Other features that may not always be included in traditional reference books are the species historical significance.

This book is really a must have for any birder, if it just serves as a reference. But, this book is more than informative. It is a pleasure to read. Not only that, but it also has some really beautiful photography and illustrations. It is a nice just to flip through and view the wonderful collection of photographs. And they are a decent size too not very small. Altogether there are over 2,000 color photos, illustrations, and maps.

The author, Christopher Perrins is Director of the Edward Grey Institute of Field Ornithology at Oxford University. But the book contains contributions from over 100 respected zoologists around the world. This book is definitely worth the investment.