This book is great value it practically gives you two for the price one. Door Supervision and Security Guarding, just what you need to get started as a security proffesional. One of the best sellers in the edition it makes a fantastic addition to training and exam preparation.
Probably the most comprehensive book ever written on the topic. The Door Supervision in The Private Security Industry Pocket Manual is available in kindle addition for download at Amazon.com. Paperback additions available subject to availability.