One of my favourite Shiv outfits is this gorgeous, plaid suit she wears in episode eight to take down her new rival-for-CEO, Rhea Jarrell (played by Holly Hunter). Shiv wears businesswear almost exclusively, but rarely does she appear in a full suit set and, even then, they're only rendered in neutral, monochromatic shades of cream, grey, or black. Since we mainly see her in sharp blazers, pressed trousers, and silk button downs in neutral palettes, this loud and printed suit is screamingly different—a visual indicator she means business.
And, truly, wouldn't you be terrified if Shiv Roy was out for your blood and wearing this suit?