The  explosive  development  of    “free”  or  “open  source”  information goods  contravenes  the  conventional  wisdom  that  markets  and  commercial organizations are necessary  to efficiently supply products. This paper proposes  a theoretical explanation for this phenomenon, using concepts from economics and theories  of  self-organization.  Once  available  on  the  Internet,  information  is intrinsically  not  a  scarce  good,  as  it  can  be  replicated  virtually  without  cost. Moreover,  freely  distributing  information  is  profitable  to  its  creator,  since  it improves  the  quality  of  the  information,  and  enhances  the  creator’s  reputation.  This  provides  a  sufficient  incentive  for  people  to  contribute  to  open  access projects.  Unlike  traditional  organizations,  open  access  communities  are  open, distributed  and  self-organizing.  Coordination  is  achieved  through  stigmergy :  listings of “work-in-progress” direct potential contributors to the tasks where their contribution  is  most  likely  to  be  fruitful.  This  obviates  the  need  both  for centralized planning and for the “invisible hand” of the market.