Integrated Development Environments: the usual free Lisp IDE nowadays is GNU Emacs with SLIME.

See also:

and (perhaps, one day, eventually) CL-Emacs, and on MS-Windows: VisualCLisp and LispIDE

And dead editors: Cusp (an Eclipse plugin), Jabberwocky (a stand-alone editor), Hemlock (an Emacs-like editor embedded in CMUCL).

Find ".emacs" files used by famous lispers! Wow! Emacs customizations

OpenMCL comes with an idea (primitive listener, inspector and editor) of a development environment based on the Cocoa libs of MacOS X.

The big hope is that McCLIM will be the base for a (portable) development environment for Common Lisp (listener, editor, debugger, ...).

Tools provided by a Common Lisp IDE:

  • Editor
  • Listener
  • Inspector
  • Apropos Dialog
  • Stepper
  • Trace Dialog
  • Backtrace Dialog
  • Restarts Dialog
  • Save Application Dialog
  • Preferences Dialog
  • Online Help
  • User Interface Builder
  • Class Browser
  • Generic Function Browser
  • System Browser
  • Package Browser
  • Process Browser
  • Mail Client (!!)