I'm headed out for a week on a Sierra Club volunteer trip and my biggest suitcase is 20"x15"x6" so packing was a challenge. The list our leader gave us specifies work clothes for the week, including boots, leather gloves, heavy denim or twill pants, long-sleeved shirts, and hat. Also clothes for hanging out in the evening and indoor shoes so we don't track in dirt. And a daypack, cooler to carry our lunches, two water bottles, first aid kit and sunscreen, and toiletries. Of course, I'm bringing a camera as well. Oh, and we supply our own bedding. The lodge where we'll sleep has only limited solar-powered energy for cooking. So brief showers only every other day and no laundry. Did I mention I only have a smallish suitcase? But I am the queen of packing lightly. I'll wear the boots on the plane and my down jacket (which is necessary getting to and from the airport here) will be stuffed into a pillowcase for sleeping once I get there. The cooler is in the bottom of the daypack and will be my carry-on. Phone, camera and other valuables will be inside the pack as well. Everything else is neatly rolled and fits nicely into the suitcase. I even packed things into the empty water bottle. Assuming I am not bitten by a rattlesnake or taken down by a pack of coyotes, I'll see you when I return.