A metal–organic framework (MOF) is a porous hybrid material composed of organic ligands and metal ions that form clusters. MOFs have gained widespread use in various research areas due to their exceptional properties, including compliant structures, abundant functional groups, high porosity, large surface areas, and efficient adsorption capabilities for capturing a range of harmful cationic and anionic species. This chapter provides an overview of recent advancements in MOFs and MOF complexes, particularly focusing on their role as MOF-based ion exchange sorbents. These materials are well-suited for applications such as dye degradation, antibacterial activity, and the removal of heavy metals from wastewater. The chapter discusses prospects, challenges, and future applications of MOFs, especially in the perspective of ion-exchange technology.