  In this article we establish an analog of the Quillen---Suslin's local-global
principle for the elementary subgroup of the general quadratic group and the
general Hermitian group. We show that unstable ${\k}$-groups of general
Hermitian groups over module finite rings are nilpotent-by-abelian. This
generalizes earlier results of A. Bak, R. Hazrat, and N. Vavilov.
