The garbage can model is based on the assumption that decision making is sloppy and haphazard. Decisions result from an interaction between four independent streams of events: problems, solutions, participants, and choice opportunities.
The Origin of the Garbage Can Model Theory (4:19)
James March on the Garbage Can Model
Interview with James March by Diane Coutu
Harvard Business Review, Oct 2006, p. 88
You're famous for your garbage can theory of organizational choice. Can you sum up the theory for us?
The original article on the garbage can theory was written jointly with Michael Cohen and Johan Olsen, so they have to share in whatever fame or shame there is in it. A fair number of people took the organized-anarchy notion that life is ambiguous and said, "The garbage can is really a label for confusion." That wasn't quite what we meant.
We were operating at two levels. On one level, we were saying that choice is fundamentally ambiguous. There is a lot of uncertainty and confusion that isn't well represented by standard theories of decision making. Opportunities for choice attract all sorts of unrelated but simultaneously available problems, solutions, goals, interests, and concerns. So a meeting called to discuss parking lots may become a discussion of research plans, sexual harassment, managerial compensation, and advertising policies. Time is scarce for decision makers, though, and what happens depends on how they allocate that time to choice opportunities.
On the second level, we tried to describe the way in which organizations deal with flows of problems, solutions, and decision makers in garbage can situations. The central ideas were that a link between a problem and a solution depends heavily on the simultaneity of their "arrivals," that choices depend on the ways in which decision makers allocate time and energy to choice opportunities, that choice situations can easily become overloaded with problems, and that choices often can be made only after problems (and their sponsors) have moved to other decision arenas and thus typically are not resolved.
In our minds, the garbage can process is a very orderly process. It looks a little peculiar from some points of view, but it isn't terribly complex, and it isn't terribly jumbled. The good thing, I think, is that our perspective has opened up the possibility for people to say, "That's a garbage can process" -- meaning it's an understandable process in which things are connected by their simultaneous presence more than by anything else, even though they look all mixed-up.