Gail commented: "I'm wondering how permaculture can exist in overpopulated areas such as inner cities.  And what does permaculture suggest that we do with all of the agri-businesses that now own so much of the land.  Does it address that?"

I replied briefly: "Gail and those with the same curiosity can start with the presentation by Janis Birkeland, which is the last item in the Learning Resources section.  That said, any urban projects that increase photosynthesis and utilization or penetration of precipitation are (more) life affirming.  So, planting as possible and de-paving to increase the possibilities are big first steps."

I've since added a link to City Repair to the Learning Resources section.

David Tracey wrote Guerilla Gardening:  A Manualfesto (2007).

Last, for now (must answer the question regarding agri-businesses), Scott Kellogg and Stacy Pettigrew co-authored Toolbox for Sustainable City Living (A Do-It Ourselves Guide) (2008).