For years, AutoLISP® has set the standard for customizing AutoCAD®. Now Visual LISP® (VLISP) represents the next generation of LISP for AutoCAD, by adding significantly more capabilities. VLISP extends the language to interface with objects through the Microsoft ActiveX® Automation interface, and enhances the ability of AutoLISP to respond to events through the implementation of reactor functions. As a development tool, VLISP provides a complete, integrated development environment (IDE) that includes a compiler, debugger, and other tools to increase productivity when customizing AutoCAD.