The Surgeon General’s report on smoking was released almost 50 years ago and people still smoke cigarettes. We know the effects of cholesterol, heart disease, and the calorie count at many fast food restaurants, yet their sales are still well. Alcohol consumption (which does have some medical benefits in moderation) leads to impaired driving and abuse, yet liquor establishments are still in business. Thanks to advances in medical research, we know what can harm us. Even with that knowledge, we still do it anyway. The same can be said about common mistakes that plan sponsors commit in their role as plan fiduciaries, errors that increase their liability, but they still do it anyway. So this article is about common plan sponsor errors that plan sponsors continue to do even if they understand the error of their ways.