I'd like to believe that the way we "think" we need to dress in a professional setting is Chanel's fault, or rather her masterpiece. From our mothers and grandmothers, we were raised to understand professional business attire for women consisted of a two piece suit with pumps or kitten heels and a button up. To be quite honest, it is still considered the norm in the office.
Our meaning of "professional" has evolved over the years, in my opinion due to the increase of creative positions and laid back technology companies who also offer sushi lessons during lunch break. Therefore, our professional style has evolved just the same. (thank you Google!) It has not drifted so far away from the business suit and heels, it has merely adapted to its time and surroundings.
For instance, when you hold a job in the fashion industry, no matter the title, you should always dress as though they will pull you onto the runway at any moment. In the marketing, pr and social media arenas, most dress in a hybrid between business and casual, a 'no heels required but we recommend it with jeans' environment. If you are in a service related industry its pretty much comfort beats style, and with good sense.
Personally, I feel a need to express my sense of style in any environment by simultaneously adapting to it. For instance, when I am covering runway, I could easily dress like the rest of the photographers and media. However, I dress like a front row occupant every single time. I do this because it makes me stand out amongst my peers as well as makes me feel productive and confident. Granted, my feet may be bleeding after a full day of New York Fashion Week, but that is what cocktail hour and Dr. Scholls are for!
So have a blast on Polyvore creating new business outfits to recreate. My suggestion to you is to dress in what is appropriate for your environment while maintaining a statement making image so that you feel confident and stand apart from the rest who may look as though they really didn't get quite enough sleep last night. And remember, an outfit can easily be ramped up with the right accessories!