DES supports design mode of Visual Studio and Visual Web Developer in many ways.

• The SmartTag feature starting Visual Studio 2005 has been extensively utilized. Each control provides its most important properties for you to edit immediately. It also has commands to display the help files associated with the controls.
  
• The original Properties Editor has a few shortcomings that are addressed by the Extended Properties Editor. Of its new features, the most important is "Best Order" mode, which displays the properties in the best order for setting up the control. It also hides less important properties.
  Here is the Expanded Properties editor on a TextBox. On the left is a normal view. On the right, it is using Best Order mode with only the important properties shown.
  
• Whether using the standard or Extended Properties Editor, properties show useful documentation.
• Many properties offer extensive editors to assist with setup. For example, the RegexValidator's Expression property provides Regular Expression testing tool, shown below.
  
• DES provides the Global Settings Editor application to edit a large list of global settings that control page-level settings, string lookup setup, and Required Field Marker defaults.