It may seem a little cliche, but in terms of winter prints it doesn't get much better than a classic plaid/tartan/whatever you want to call it. Also, plaidfit needed to become a thing like yesterday.
Have worn this little number MANY a times in and outside the the big boardrooms and fancy cocktail bars. Sexy, conservative, and very much incorporates a more "fashion-y" look which is TOTALLY OK to do. Just make sure that when wearing a fitted pencil skirt (especially if you have a peach like moi) wear an extra-conservative top to balance it out.
Bag: Kate Spade