jscols is a JavaScript collections library providing implementations of Lists, FIFO queues, LIFO Stacks, Priority Queues, sorted and unsorted Sets and Maps, Bags (Multi Sets) and Multi Maps. The goal of the project is to add functionality to the JavaScript language, similar to that of java.util.Collections (for Java) and the C5 Library (for C#). The Library stands alone and should be easy integratable in all kinds of JavaScript projects. Even though the jscols library is independent of other libraries, it integrates especially well with the google closure library, as method names generally correspond to the generic collection operations of goog.structs. This also includes the way goog.structs support closures.