The Rare Earth Research Conferences (RERCs, North America) alternate on a three-year cycle with the International Conference on f-Elements (Europe) and the International Conference on Rare Earths (rest of the world). The 29th Rare Earth Research Conference in Philadelphia follows the successful 26th RERC in Santa Fe, New Mexico (2011), the 27th RERC in Squaw Valley, Nevada (2014) and 28th RERC in Ames, IA (2017).