[Greenbuilding] basement insulation

[Paul Newby]

I'm attempting to come to an understanding of the
best option to insulate the inside walls of a
walk-out basement in a cold climate taking into
account moisture control.  I presume you need to:

   1) allow an evaporation path for moisture coming
from the outside (through the walls and footings); and

   2) prevent moisture from entering the wall from
the inside.

I don't see how you can (easily) accomplish both
objectives at once.  An insulation contractor recommends a
layer of spray foam applied directly to the inside
concrete walls.  If the foam has a low vapour permeability,
you accomplish 2) at the expense of 1).  If it has
a high vapour permeability, you get 1) but not 2).
I would think that the best solution would be to
opt for high permeability and ensure a low humidity
environment within the basement living space so that
any moisture accumulation that may occur during
the cold season evaporates out during the warm seasons...?

Thanks in advance for any insights/suggestions.

Paul N.