Korean drama's with in-detail job depictions

Drama's that show in-depth scenes of work-related situations.
Like in "She Would Never Know" where you see them brainstorming over how to get the best marketing strategies for beauty and health products.

I personally love seeing different jobs depicted in drama's.
If you like this as well, please list drama's with in depth job depictions below. Also vote for your favorite one while your at it, but base it on which drama you think has the best in-depth job depiction.

(No limit to how many you can list)