Over the past four decades, many scientists have made notable advancements in both the theory and application of ion exchange. Pioneers continue to break new ground by synthesizing novel materials and creating interdisciplinary connections across science and engineering. The seven chapters assembled in this latest volume reflect contributions from researchers across the globe. This volume testifies to the growth in the field and the synergies it has created with a myriad of scientific endeavors, from decontamination to deionization, mining to microelectronics, and drug delivery to desalination, to name just a few.