Just letting people know about this in case it is of general use to others. I have just finished creating a spreadsheet for converting lists of points with Cartesian (X,Y,Z) coordinates into survey leg format data which can be processed with Therion or Survex. Yes I realise that Survex and Therion can process cartesian format data directly, but sometimes you have some data extracted from some old project (or measured off something plotted to one map grid) and you want to apply a declination correction to convert to another grid, or maybe just see what the original survey leg data might have looked like. Published on the UK CSG website: http://cp.cavesurveying.org.uk/index.php/articles Footleg