A diagram - choose your flavor - that describes the current/past/future state of the system or design issue.  

It does not have to be detailed or extensive.  
It should be only as extensive as necessary.  
It should be visible to the whole team, easy to manipulate, and easy to point to. 
It can express the current system, the old system, the future system, the proposed system.  
As development focus shifts from one area of the system to another the document can shift, IOW it's not a permanent diagram.  

Our LivingDesignDiagram is on a large whiteboard.  It currently has the core business classes and relationships on it.  We've chosen four colors to represent the different states of the design:
	* Black - Current design
	* Green - Future design  (Something we all know is the right thing to do at the right time)
	* Blue - Current but Deprecated design (should not be extended/duplicated and will soon be refactored)
	* Purple - Proposed design (Just ideas that could eventually be put into action)

Has anyone used one of these or something similar?  It is very helpful in communicating and planning and designing.
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	* Red -- For what's being actively worked on in the present moment (we actually used Green (for "growing"), and Red for current problem or risk areas, but those are spoken for above). --DaveSmith

''Does '''In flux''' mean someone has claimed that task? And '''Problematic''' means be careful?''

Maybe that's how this can be tied to planning or task management, huh.  It would be nice to tie planning, design, and communication together in one succinct picture.

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If needed, even without an ElectronicWhiteboard or PrintableWhiteboard and without spending a lot of time copying it down one can take a WhiteboardPhoto
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