Since the 1990's, Calvin Klein has become synonymous with underwear, making the American designer a go-to when shopping for those basic essentials. Blending comfort and practicality with the sensual and seductive, Calvin Klein underwear is both functional and fashionable. This line of basics includes everything from push up bras to lacy briefs, so whether you're looking to show off or cover up, you'll find the underwear for you.