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This chapter is excerpted from ‘Statistical Process Control for Managers'. Davis Balestracci recently wrote, 'When I look at training materials or books (on statistical process control), their tendency is to bog down heavily in the mechanics of construction without offering a clue about interpretation.' 1 If you have been frustrated by very technical statistical process control (SPC) training materials, then this is the book for you. This book focuses on how SPC works and why managers should consider using it in their operations rather than on how to calculate limits for control charts. It provides the reader with a conceptual understanding of SPC so that appropriate decisions can be made about the benefits of incorporating SPC into the process management and quality improvement processes. An extensive list of references is provided for those readers who wish to dig deeper into the technical details of SPC. SPC is designed to facilitate making better, more informed decisions about processes. SPC can indicate whether a process should be adjusted or left alone. It can also indicate when a process needs improvement to meet requirements, often can indicate a starting point for improvement projects, and can also provide documentation of the results of process improvement activities. SPC as we know it was developed by Walter Shewhart in the 1920s and 1930s. Properly employed, SPC can be a significant factor in the control and minimization of variation in the manufacture of products and the delivery of services. It can greatly reduce the time it takes to recognize problems and provide information useful in the identification of root causes of those problems. SPC is also useful in demonstrating that a process is capable of consistently delivering what the customer wants. For this reason, some organizations require their suppliers to use SPC in order to become preferred suppliers. SPC also can provide conclusive evidence for the effectiveness of continuous process improvement programs. The concept of SPC is relatively simple and with today's modern software packages, the mechanics of using SPC are simple. But that simplicity can lead to problems. With modern software packages anyone can create control charts from data without understanding the key concepts that make those control charts useful, how to interpret the charts they create, or how to use the information the charts provide to improve processes. The purpose of this book is to provide the necessary understanding to effectively utilize SPC to improve quality and consistency of both products and services. Because today there is little need to make the necessary calculations by hand, the book focuses little attention on manual calculations. Rather, the book primarily utilizes Minitab and NWA Quality Analyst, two of the most popular statistical analysis software packages on the market. Links are provided to the home pages of these software packages where trial versions may be downloaded for evaluation and trial use. Unlike statistics and statistical quality control textbooks and manuals, this book does not address the tedious topic of how to construct control charts by hand. Instead, it covers the basic statistical concepts behind control charts to provide basic understanding of what is going on and then discusses the basics of using software products to create the charts. The book also addresses the question of why SPC should be considered for use, the process of implementing SPC, how to incorporate SPC into problem identification, problem solving, and the management and improvement of processes, products, and services. Examples from my 25 plus years of experience with SPC are included to illustrate main points in the book. References are also included for readers who wish to delve more deeply into the technical aspects of SPC.