Whether in public or in private, I always go commando - I don't own any underwear and the majority of my friends don't own any, either. I've been going commando for more than half my life, and there simply aren't any disadvantages to going commando. Now, while I essentially concur with what Kenneth P said, I feel there are a few things that need clarification. First of all, yes, there are certain rules of hygiene you should adhere to. However, if you don't, it still isn't going to make a difference whether you wear underwear or not. Contrary to common belief, underwear isn't an impenetrable barrier that keeps microbes in. To micro-organisms, the thin fabric that underwear is made of is like being a flea in an elephant's cage. What under wear *is* very "good" at, however, is preventing sweat from evaporating (throughout the year): thus, a humid, warm environmet is created that actually helps micro-organisms to proliferate. Wearing underwear under your jeans for 16 hours is bacteriologically equivalent to wearring those same jeans commando-style for several days (up to 4). So you save on washing not just by not wearing underwear, but also because you can wear the same pair of trousers longer. 2nd misconception: if you observe the afroementioned rules of hygiene, the genital area of men is very clean, much cleaner than, for instance your hands or mouth. So as far as hygiene is concerned, underwear is actually less hygienic. What's more, and as Kenneth mentioned: underwear will overheat your testicles. However, this isn't just bad news for your sperm cells. Testicles are the primary source of male hormone in the body. If testicles are permanently (read: several hours a day) overheated, the body will first try to normalise temperature by letting the cremaster muscles relax. If that doesn't work, it'll decrease the blood flow to the genital area. Which, in turn, doesn't only lead to a decrease in flaccid volume, and as Kenneth said, muscular atrophy (it's more the constant overheating, than the support that causes this), but also to a decrease in male hormone production. The very hormone that makes men, men. This decrease leads to a whole series of effects. And yes, you may have concluded: wearing underwear (any type, not just briefs) does decrease your gential volume when flaccid. Conversely: yes, going commando will (not: can) make "things" bigger over time (provided you never wear underwear for a prolonged period). And yes, those muscles will start to develop again, resulting in a more muscular scrotum (and not a floppy sac, as many believe) I have never seen any need for underwear. They are mainly a marketing ploy, and it's interesting to note that, ever since their introduction to the public at large (some 90 years ago), there has been a steady drop in fertility of men, and a doubling of cases of testicular cancer every decade. In short: there isn't a real contradiction here. Underwear is not an alternative to going commando, and there aren't any *actual* disadvantages to going commando. It's just sexual insecurity that makes men stick to their undies. Going commando is much healthier, much more comfortable, much more hygienic, much more convenient, and yes, sexier too.