Three years ago, the authors accepted positions as high school principals in Buffalo City (NY) Schools after serving as elementary school principals in the district for many years. In their new positions, they were to lead schools that were designated by the New York State Department of Education as "persistently lowest achieving," better known among New York educators as "PLAs." South Park High School and Bennett High School are still PLAs, but over the past three years, South Park has reduced tardiness between classes dramatically; short-term suspensions are decreasing; and more South Park students are graduating--in 2011, the graduation rate increased by 11%. About the time they accepted their new positions, Buffalo Public Schools put its Positive Behavior Systems model into place. The terms "positive behavior support and positive behavioral interventions and supports" (PBIS) describe any set of strategies or procedures that improve behavioral success by using nonpunitive, proactive, instructional, and systematic techniques. First and foremost, PBIS strategies work effectively to change a school's climate and its culture. ["Significant Steps Forward" was written with Sharon Comerford.]