Pythagoras has all cogo features you will ever need. Intersection, resection, open and closed traverses, coordinate transformations, coordinate reference systems, you name it. More importantly, Pythagoras does cogo in the background while-you-draw. Pythagoras accurately keeps track of the complete geometry of the drawing. All information you will ever need is derived from the geometry - coordinates, bearings, distances, slopes, angles. The geometry is a logical result of the drawing. It's always accurate, and it avoids mistakes.