Personally, I feel "space/emergency" blankets do have a place in your emergency "kit/supplies". We use them on actual rescues often, mainly as an outer vapor/wind barrier. When encountering environmental situations which might lead to a potential hypothermia condition, let us exam some of the causes, preventions and treatments, to see if these blankets have a place in your kit, before we discard them as minimally useful. It is a misnomer that hypothermia occurs only in cold weather conditions. In fact hypothermia occurs when the body is unable to maintain a viable core temperature. Environmental conditions, which are cool and wet, are often encountered in the springtime. A rainy, cool (50-60 degree F) day is perfect weather for the development of hypothermia. When one's clothing becomes damp from perspiration or wet from rain, falling in water, etc., unless they are made from wool or synthetics like polypropylene/fleece they will lose their insulating properties, that is why many of us frown upon cotton clothing. If there is any breeze or wind, heat loss from evaporation and convection will be increased greatly. Sitting on the cool/cold ground or rock will conduct heat away from the body. Little to no energy from the body's energy reserve will also play a factor in the development of hypothermia. So are these blankets of any use? Yes, as indicated they can provide for little weight a valuable vapor barrier and wind block. When combined with an external heat source (heat packs, warmed rocks, warm body, etc.), dry clothing and other insulative items (coats, blankets, etc.), will trap warmed air, resulting in the reduction of body heat loss. Set up a tarp, poncho or body wrap can block rain and wind. They can also be used to collect rain water, cut into smaller sections for occlusive dressings, cut and folded into strips, as a substitute for cravats, trail markers, etc. For the money and weight, I feel they are a definite addition to one's supplies, as long as you understand their uses and limitations. Pete