In the past two decades, companies have increasingly relied on Agile methods to keep up with growing demand and changing markets; today, about half of all companies that use Agile use Scrum. Over the years, we have observed Scrum's adoption at companies new to these ideas, as well as renewed/continued interest even in experienced Scrum/Agile organizations. We have also noticed a trend that companies have adopted subsequent processes—Extreme Programming, Lean, Kanban, and others—usually after initiating Scrum first.

Jeff Sutherland first used Scrum at Easel Corporation in 1993, and subsequently used it at companies such as VMARK, Individual, and IDX Systems throughout the 90s. Ken Schwaber, who worked with Jeff at Individual, 'formalized' Scrum at the OOPSLA Conference in 1995. At the turn of the millennium, Jeff famously applied Scrum at Patient Keeper and Ken helped scale Scrum at Primavera Systems, the latter whose case study was made popular by an online whitepaper and several anonymous mentions in Ken's second book, Agile Project Management with Scrum.

However, these early applications in the mid to late 90s weren't the first rumblings of Scrum. In 1986, Harvard Business Review published an article by Hirotaka Takeuchi and Ikujiro Nonaka entitled The New Product Development Game, in which the authors wrote that development organizations must extend their focus beyond scope, time, and cost to find ways to increase speed and flexibility of product delivery in order to win in the new competitive landscape. Instead of the relay race, "…a holistic or 'rugby' approach – where a team tries to go the distance as a unit, passing the ball back and forth – may better serve today's competitive requirements." This article was the first mention of Scrum as a new paradigm for product development—a thought framework for quick, flexible, and competitive product development. It's important for ScrumMasters to remember that Scrum practices—a set of work steps, outputs, and artifacts—are nothing without the underlying mind-set and concepts toward product development that Takeuchi and Nonaka set out to describe: built-in instability, self-organizing project teams, overlapping development phases, multi-learning, subtle control, and transfer of learning.

The concepts behind Scrum go even further back in time. In the 1950s, a management consultant by the name of W. Edwards Deming created the Plan-Do-Check-Act (PDCA) cycle as a framework for continuous improvement. PDCA, also known as the Deming or Shewhart cycle, had an early influence on Toyota's lean approach to manufacturing. These ideas map one-to-one to that of a Scrum's sprint, and even to a sprint's daily scrum, as indicated in the following figure and later in the book, but Deming didn't know he was doing Scrum. Or more appropriately, perhaps, is that today's Scrum teams don't readily realize that they're applying the Deming cycle!

Scrum's foundation is even older than Deming. Go back 1,000 years to when Alhazen, a Muslim scientist and mathematician, ran experiments with reflection, refraction, lenses, and mirrors, thus deriving some of the principles of optics (captured in his book, The Book of Optics). Alhazen is considered by some to be the father of the scientific method (http://www.wikipedia.org/wiki/Scientific_method), a process through which a scientist creates a hypothesis or asks a question, runs an experiment, discovers results or gains knowledge, analyzes the findings, and possibly modifies the hypothesis (or decides to run a subsequent experiment). This empirical, or evidence-based, process is one in which a person will use knowledge gained from one experiment to draw conclusions or influence the next experiment, like the process by which Alhazen discovered the basics of human eyesight.

Finally, if we go a bit further back in history, you could imagine that even a primitive tribe's hunting session looked a lot like a Scrum sprint: everyone gathered together, grunted about where to stalk the prey, gathered up their hunting tools, killed dinner, and then talked about the hunting experience, which improved the plan for next time. We see evidence of these primitive retrospectives in cave drawings around the world. Scrum a most natural way of working that relies on the collaboration and close work of people to achieve an outcome. It's been this way for at least 11,000 years. We'll explore in later chapters why, even though it reflects a natural approach toward work, Scrum is so challenging.