I use a compass for dead reckoning (distance and azimuth) in flat, forested terrain. I use it for orienting my map so that I can be sure that it is Suggs Peak at which I am looking not a peak 180° the other way (don't ask!). And, I use it for triangulation to find my location on the map. If I am in familiar country such as the Sierra and have a good map then I seldom use a compass other than just to keep the thing from getting rusty. But, working in forestry in the PNW lowlands gave me a good foundation of basic land navigation skills and the skills are still with me. I always have a quality sighting compass with me on my trips. I also know how to use a GPS unit (6 oz) but generally have less use for one of them than I do a compass (0.8 oz); YMMV.