Nicotine is a drug with a wide variety of effects — effects that are not black or white or even a shade of gray. Rather, the multifaceted effects of nicotine form a checkerboard pattern of effects, some of which are adverse, such as promoting tobacco smoking, and others that may provide therapeutic benefit, such as cognitive improvement and pain relief. To understand nicotine’s effects, research must progress on a spectrum of levels from nicotinic receptors through complex neurobehavioral systems to clinical outcome. This book presents research approaches to all of these levels. Considerable progress can be made by integrating research across traditional disciplines so that novel nicotinic ligands discovered in receptor studies can be used in experimental animal models to gain information about specific nicotinic systems involved in behavioral function. This functional understanding can be used to develop better nicotinic-based therapeutic treatments.