You only get one first impression - so make it a good one. Not only will your peers/superiors judge you based on your attitude, demeanor, and work ethic, but your apparel as well. Per the request of some followers, we've put together a general list of what is - and is not - appropriate for a work environment. We're open to additional suggestions or constructive criticism.
Don't forget the time-honored seersucker traditions on the Hill: "Seersucker Thursday" in the Senate and "Seersucker Wednesday" in the House.
Ladies. You should aim to include three primary pieces in every outfit - skirt/pants, shirt, blazer/cardigan. As interns, it's difficult to build a work-appropriate wardrobe on little-to-no income. However, purchasing just a few simple, classic pieces will allow you to mix and match to create multiple outfits out of what was previously only one or two.
Shirt. If the shirt is extremely conservative (a buttoned oxford, long-sleeved silk shirt, etc.) you can probably pass without a blazer or cardigan. However, as a general rule, try to include a blazer or cardigan with every outfit. Sleeveless shirts or dresses (without a cardigan or blazer) are never appropriate.
Cardigan/Blazer. A few staple blazers and cardigans (black, navy, pink, cream) can go a long way. They will coordinate with just about anything and will provide you any additional coverage necessary.
Skirt/Pants. Skirts should always pass the fingertip test and should be no more than 1.5ish inches above your knees. If the skirt is higher than mid-thigh when you sit, it's too short for the workplace. Don't forget about the vent in the back - it, too, should not be too high nor should it ever allow those walking behind you to see "through" it (the flaps should overlap, not create a "V" shape). This should go without saying, but don't wear leggings.
Shoes. Three-inch heels are about as high as you should go.
Recess Attire. If you wear jeans during recess, try to pair them with a cardigan or blazer. Sweatshirts, flip flops, and mini skirts are not appropriate at any point (recess or otherwise).
Guys. Guys have it a bit easier: Wear a suit. Make sure if you're wearing a brown belt, you're wearing brown shoes (the same goes for black). Try to avoid clashing your suit/shirt/tie. Keep it simple. Never, ever wear white socks with your suit - solid or "fun" dress socks can be appropriate, just avoid athletic socks. Socks should coordinate with your suit and shoes (back to the don't mix black and brown rule). During recess, wear a collared shirt tucked in (no tee-shirts, sweatshirts, etc.).
We think that about covers it!