A definition:
  
  Organizational development is a top-down 
  management-supported, long-range effort to improve an 
  organization's problem-solving and renewal processes, 
  particularly through a more effective and collaborative 
  diagnosis and management of organization culture, with 
  special emphasis on formal workteam, temporary team, and 
  intergroup culture, with the assistance of a consultant - 
  facilitator and the use of the theory and technology of 
  applied behavioral science, including action research.
  
  
  Kurt Lewin was a founder of the Organizational Development 
  (OD) movement.  He described organizations as existing in a 
  state of "quasi-stationary equilibrium",  which means they 
  tend to be stable and resist change.
  
  Lewin felt the OD specialists task was to  (1) unfreeze the 
  organization, (2) change it, and then (3) refreeze it in the 
  new configuration.
  
  He utilized a method called "action research", which is much 
  like scientific research, except that adjustments are made in 
  the research strategy as feedback is obtained.