This chapter provides an overview of topics covered in the book and discusses the basic problems associated with obtaining accurate survey counts for wild animals. It highlights the overall need for the accurate detection and counting of animals to ensure precise estimations of animal populations so that proper management goals for large and small populations and even rare species can be met. The basic concept of detect ability and its importance to the fundamental aspects of wildlife management is introduced. The chapter also includes a brief review of why thermal imaging is desirable for observing animals in the wild as opposed to other methods of observation.