This book entitled Zeolites is a collection of papers recently published in the journal Crystals, focusing on zeolites as a group of hydrated aluminosilicates with unique physical and chemical properties that can have numerous and important applications. The collection opens with works related to the geological documentation of the newest deposits of natural zeolites. The second part of the book describes a variety of synthesis methods and characterizes the resulting products. Finally, some recent advances in their applications in different fields are presented at the end of the book.