1. Introduction 2. Technology overview of electrodeionization 3. Configuration and mechanism of electrodeionization module 4. Construction of Electrodeionization 5. Application and comparison of Electrodeionization 6. Heavy metal ions removal 7. Electrodeionization in Desalination and Water-softening 8. Production of high pure water using Electrodeionization 9. Advances future scope in Electrodeionization 10. Economics and environmental aspects of the EDI technique