Back in my salad days I was issued a ALICE pack. I hated it but it carried a lot-and was one big compartment. I guess about 25 years ago the military switched to a modular system called MOLLE. And about 3 years ago I got a MOLLE pack for Christmas, and I'm still impressed by MOLLE versatility. There are strips running all around the pack that I can attach many pouches of just about any size. The beauty of the system lies in the fact that I dont have to carry what I dont need. I put my raingear in a pouch on the outside of the pack; if there is no chance of rain I can leave that pouch at camp. If the forecast calls rain and then colder weather I hook that pouch on. If I'm gonna stay out well after dark the NV gear pouch goes on maybe the rain gear, food and book pouches come off. The result is that with MOLLE I can leave gear behind that I dont need. I get a lighter and more accessible pack. If vso inclined a person could put put together tactical pouches.