When I first received this book, I was overwhelmed by its size and weight - it is bigger than the typical field guide. However, after using it for one week in Mexico I was won over. It contains a wealth of useful well-organized info, about each species, plus plates and drawings which are both beautiful and carefully accurate. I found myself reading in it extensively nearly every evening, just for pleasure. Helpful tip: supplement it with a standard North American field guide. Common NA species which occur in Mexico and Central America are not always pictured in plates or drawings, though they are clearly described.