Critical Steps happen every day at work and at home, purposefully. Work does not happen otherwise. If an operation has the capacity to do work, then it has the capacity to do harm. Work is energy directed by human beings to create value. But people are imperfect—we make mistakes, and sometimes we lose control of the work. Therefore, work is the use of force under conditions of uncertainty. A Critical Step is a human action that will trigger immediate, irreversible, and intolerable harm to an asset, if that action or a preceding action is performed improperly. Whether the human action involves clicking on a link attached to an e-mail message, walking down a flight of stairs with a newborn baby in arms, engaging the clutch on a gasoline-driven chain saw, or administering a medication to a patient in a hospital, these all satisfy the definition of what constitutes critical risks in our daily lives, professionally or personally. The overarching goal of managing Critical Steps is to maximize the success (safety, reliability, productivity, quality, profitability, etc.) of people’s performance in the workplace, to create value for the organization without losing control of built-in hazards necessary to create that value.