A quadratic form over a Henselian-valued field of arbitrary residue
characteristic is tame if it becomes hyperbolic over a tamely ramified
extension. The Witt group of tame quadratic forms is shown to be canonically
isomorphic to the Witt group of graded quadratic forms over the graded ring
associated to the filtration defined by the valuation, hence also isomorphic to
a direct sum of copies of the Witt group of the residue field indexed by the
value group modulo 2.