Layer 1; moisture wicking base layer.
Layer 2; ScentLok BaseSlayers
Layer 3; PolarTec heavy weight thermals
Layer 4; Adaptation Fleece (BassPro)
Layer 5; (if needed, another heavy fleece pullover)
Layer 6; Wolfskin Enigma

I know 6 is quite a few layers, but it's not bulky at all. It does, however, take about 20 minutes to get dressed every morning....[&:]