The hotel is not "on the beach" but I was visiting recently and they like to say the hotel is "two steps" from the beach - one step on the shuttle, and one step off. Not sure how frequently it runs, but it's Kaua'i - are you late for a business meeting? :-)

The property itself is gorgeous - there are several pools (one of right is right on the edge of the sea cliff - fabulous!) and there are grills around the property if you feel like cooking in one night. The drinks are of course pricey, but do enjoy at least once sunset in the bar at the St. Regis, and try their Aloha Mary.