Hi, after a little advice please. I am relatively new to AutoCAD and I work in the Civil and Marine Engineering sector. I have recently been asked to help out on a project which requires accurate dimensioning for clearances, etc. I have been using the As-built drawings to gather the required dimensions, by measuring in the CAD drawing. Is this ok to do? As I have been informed, by one of the engineers that we shouldn't measure off the CAD drawings, but to work out the required dimensions using given dimensions for other parts of the drawing. I have checked other dimensions within the drawing and they all match up. What is best practice please? Any help gratefully received.