The book describes in detail the various types of count models used by statisticians and researchers. At 572 pages in length, nearly every model discussed in the literature of count models is addressed. For each model the book shows how the model is derived, how to construct a proper modlel for a given type of count structure, how to interpret the model, and how to evaluate it in comparison to other models. Stata and R code is used for most all models described in the book.