You can do it either way; we actually do most of our excursions on our own. We just use the inter net and get into about the varies ports. I don't recommend it for first time cruisers or if the excursion is going to be an all day affair. The ship will not necessarily wait for you. Last Jan we almost missed it and I was a nervous wreck, but for 3 or 4 hour tours the selection is better, the service more personalized and price much lower. just our opinion. We usually end up with others from our ship booking with us.