James from London, U.K: I started my first professional job out of University and the dress code is very strict– basically suits and ties everyday. I’ve invested a lot of money into dress shirts and trousers, but I have no idea what to do about undershirts. We have to dress up, but working late, our sleeves are rolled up and our ties are loosened, and a few of my co-workers have commented on how my undershirts appear quite sloppy. I had no idea your choice of undershirt was even noticed, and I’m tired of being the butt of office jokes. Can you help me find something more appropriate?
The Underwear Expert: James, you have nothing to worry about. While cheaper undershirts can do the job of being your first layer, if you invest a bit more money, you’ll see your problems disappear. Many underwear companies have been playing with the construction of undershirts so they are less noticeable, such as widening and lowering the neckline, shortening the sleeves and lengthening the bottoms so they stay tucked in.
The Collected Threads jT undershirt ($11.99) basically goes unnoticed on your torso, while keeping the sweat in and remaining comfortable. Another choice is Tommy John ($40) who have a shirt that guarantees to stay tucked in. Equmen ($99) has a line of undershirts that are a must, with their seamless craftsmanship and the ability to help maintain posture throughout the day.
Collected Threads jT is an evolved undershirt. They take care of every problem from exposed collar lines to falling out with its new age construction. These shirts stop sweat and are made with shortened sleeves, lowered tails and wider collars. 
Equmen's undershirts are made to help you get through your day. The material is moisture wicking while the fabric and structure helps with posture.
The Tommy Johns Second Skin collection will feel like it's not even there. There is an extended tail to stay tucked in and it hugs your body, so people won't see it through your clothing.