Seconding this guy's advice that: >Your worst enemy really is you burning all your gas too fast, btw. You and your opponent will both experience a massive adrenaline dump. Resist the urge to spend all your energy in the first couple minutes. Get in good cardio shape, make the other guy spend his gas first. Most people in a fight 'will' spend their gas in the first couple minutes. If you've still got yours when they run out of steam, you're in a major position of strength, regardless of any martial techniques you may or may not know. I'll take slight issue with the recommendation for BJJ/Jiujitsu as the best street fighting technique. Ask anyone with real BJJ training who knows the difference between tournament and street fighting -- they'll tell you it's best to keep the fight off the ground in a street fight. On the ground, you can get bitten, eye-gouged, stabbed, and kicked by your opponent's buddies. And since you're likely to be on concrete or asphalt, even in the best of outcomes you're going to get ripped up. With careful technique, you'd be surprised how effective you can be at keeping the fight on its feet. So, boxing -- especially Muay Thai boxing -- is the absolute best first line of defense. That said, if the fight does go to the ground, BJJ and wrestling are far and away the most important disciplines to know. I'd suggest starting with wrestling, since you can learn the entire body of wrestling knowledge in a short time (mastering it is another thing), and wrestling basics translate directly to more advanced Jiujitsu techniques. Lastly, to parrot the advice you've always heard, if it's at all possible, avoid fighting. No matter what you know, you can always end up on the wrong end of a street fight -- and this can, and often will, result in permanent damage to your delicate flesh. This is especially true when you don't know who you're up against -- or what's in their pocket. I live with a permanently fucked up eye, a crooked ring finger, limited wrist flexibility, and a ridiculously crooked nose due to stupid fights that, with a couple of exceptions, I could have avoided. Believe me, if I could go back, I'd so happily swallow my pride and walk away when that was an option. The other reason to walk away is that even when you win, you can lose big time. Years ago a drunk jackass flat-out sucker punched me in a bar -- he ended up with a massive gash on his face that required a shitload of stitches. Long story short, this douche had the temerity to drag me through the courts for a over a year. His girlfriend lied admirably and managed to convince a judge I'd started the fight. Had to pay his very expensive medical bills and was lucky to get away with a prayer for judgment. And I've been lucky -- I could tell other tales of folks I know whose outcomes were far worse. So, boxing/Muay Thai combined with wrestling/BJJ are arguably the best fighting techniques you can learn. But if you can help it, don't fight. Far too much risk for far too little reward. Be cool, live long.