It really depends on the destination. On my last trip to Cuba, half my luggage was filled with used clothes to give to my friends, because clothing is so expensive in their country. I love cruising, and most times it's smart casual. If the laundry service is "cheap," I don't need to take as much as I usually do, but also use vacuum packs. I take three washable underpants, and rotate them. I try to wear each piece of clothing (except sox) three times. I also take along my camera with two extra batteries, my iPad mini, my cell phone(s), MP3, kindle, and charging wires with necessary socket converter. My two luggage measures 22x14x9 and 16x14x9, (both on wheels) and it doesn't matter the length of my trip.