It seems the more I trade the more I realize that sound money management and risk principals are essential for successful traders. I'm curious as to what rules the pros apply to themselves. I've heard it argued that one should only trade with a certain percentage of their capital to leave the bulk free to defend potential positions. I've heard some argue that one should risk no more that 1 to 3 % on any given trade. A broker friend recently informed me that most retail accounts blow out after three weeks. This isn't surprising as most are trying to day trade the e-mini with 5 k in capital. On these ag boards traders appear to have much more longevity and wisdom. To those wise traders who make a living doing this would you be kind enough to share your theories on money management?