I never travel for longer than two weeks and haven't gone any where cold for a few decades so I am good packing a pair of shorts, jeans, for under armour t-shirts, four pair of underwear, one polo shirt, Asics running shoes, one dress shirt, hair brush, toothbrush, and a pair of socks into whatever back pack currently carries my computer. I wear a pair of shorts, t-shirt, polo shirt, sweat shirt, teva sandals, G Shock watch and a Wisconsin Badger's baseball cap turned backwards. This covers all occasions, can be carried on and fits under the seat in front of me. I have yet to pay any luggage fees for my own personal items. My wife will fill two large suit cases for a four day trip. My kids have followed my lead although I usually have to make sure that they clean the clothes before they pack them.