Original User: rfairhur24You will most likely never get absolute 0 accuracy of a projected point on a line. The Resolution and Tolerance predetermine the exact level of imprecision you want to allow. You can continue to increase these settings, but any values lower than those settings will be accepted by the system and acceptable equivalent positions. I believe at 15 significant digits you will reach the limit of the double precision field is capable of storaging. But that comes with the cost of severely limiting the total world XY coordinate system your data can accommodate. Points will always move to actual XY positions that can actually be stored on the exact coordinate values those settings can create. The computer is binary and that makes certain values that can exist along a line with any slope beyond pure horizontal or pure vertical on whole number positions very hard to represent in the significant digits of fractional values. That is why you will see fractional values on point XY coordnates that are below your tolerance settings as the computer tries its best to represent the number within the binary system precision.I would test what you have in the GE Smallworld application to see what level of tolerance they accept. They have to accept some tolerance, since it impossible to store infinitely precise coordinates in a binary computer system. Their line won't exactly fall at every infinite position along the line's length either, since they have to store coordinates somewhere. I believe they would have use a non-standard field storage type to exceed the top precision ESRI supports.