Guys thanks for your recommendation of the PlayBook, glad to see it's well thought of. For those considering it you'll notice nearly every sound an elk makes is mentioned in the Book. (Bulls & Cows) The Book defines each sound & helps hunters to understand the message elk are relating to one another under varying situations & rutting phases. If some are unaware of the many sounds elk use then you may want to consider the Sounds By The Elk CD along with the Book. This CD has all the sounds referred to in the Book, this way when you come to an unfamiliar sound discussed in the Book you can listen to it on the CD to become familiar with it & it's identity. The two go hand in hand. The sounds are on separate tracks so you can choose individual sounds out as you see the need without listening to the whole CD. It also comes with an MP3 disc that can be downloaded onto any player or Iphone. Just some food for thought. Thanks.