Each year, an astonishing number of lives are lost to suicide which highlights an imperative that research efforts and attention be focused upon understanding the causes and contributing factors in suicide.  The present volume approaches suicidal behavior and ideation from many different perspectives, which, of course, is necessary because of the complexity associated with these phenomena.  In the present chapter, concepts and research efforts that will be discussed in detail in later chapters are introduced and encompass the areas of epidemiology and predictive tools, risk factors, and clinical and preclinical neurobiology.