A real cirlce cannot be drawn in Flash because of how round lines in Flash uses quadratic bezier curves. The best that can be done is an approximation. Most approximations of these types, though, are more than satisfactory for their purposes. This example gives a slider allowing you to adjust the accuracy of a dynamically drawn circle. The higher you go, the closer to a real circle you become. At about 10, you see virtually no further differnence. 8 is commonly used and 6 is good for smaller circles... even 4 can be used for very small circles, or anything small you at least want to look "round".