A slippery slope is an illustrative scenario in which events progress from an initially innocent step to a cascade of subsequent misfortunes. Each development that sequentially follows is increasingly inevitable, difficult to stop and more harmful than the last. The result is an unpredictable catastrophe. It warns participants of the possibility of unintended consequences from a seemingly innocent or valid opening action. Most of the time a slippery slope argument is criticized as a logical fallacy, e.g., if we allow our children to choose the movie this time they will, consequently, expect to be able to select the school they go to or the doctors they visit. Other times it is said to augur a political, legal, tactical threat, e.g., the U.S. government in the 1960s posited that if one country in a region became communist, the others would inevitably follow, and then all would fall into the sphere of the Soviet Union.  These exercises are dismissed as being excessively fantastical stretches or falsely deterministic. The popular and medical literature, however, make no reference to medicine's Slippery Slope.  There are no popular titles that mention it or the Shared Decision Movement, the main bulwark against medical misadventures. Every hour, thousands slip from a comfortable and healthy status to an arm-flailing, knee-buckling, body-spiraling, face-to-the-floor catastrophe.  The book addresses this quick but preventable spiraling of good health into medical disaster. My goal is to inform the readership about The Slope and to provide the tools to avoid it or to successfully slalom their way down it.