Lack of diversity in physics and other STEM PhD programs is a chronic issue. In recent years, less than 7% of domestic physics PhDs awarded nationwide have gone to students from underrepresented minority (URM) groups, even though they make up 35% of the college age population. Increasing diversity in a physics PhD program can be difficult, especially if the program receives a low number of “traditionally qualified” URM applicants. Inspired by successful STEM Bridge programs at San Francisco State, Fisk-Vanderbilt, and Michigan, the Ohio State University MS-to-PhD Physics Bridge Program (OSU-BP) was established in late 2012 with unanimous faculty support to increase the pool of qualified applicants from underrepresented groups, and accepted its first cohort of four Bridge students in August 2013. I will discuss activities and events that preceded and followed the creation of the OSU-BP, which have coincided with an increase in the representation of URM students in the OSU Physics PhD program from less than 5% of domestic students in 2012 to almost 20% in autumn 2017. These include building a core group of committed faculty colleagues, partnering with the American Physical Society Bridge Program for nationwide recruiting and other support, working with colleagues in Physics Education Research (PER) to develop new graduate physics academic support programs, and expanding holistic PhD admissions practices. I will also discuss on-going and future efforts, opportunities, and obstacles for increasing diversity in graduate programs at OSU and elsewhere. I would like to acknowledge the essential contributions of OSU Bridge Program Co-Director Jay Gupta, PER colleagues Andrew Heckler and Chris Porter, and many other colleagues who worked so hard to help these efforts succeed.