One last question and I'll leave you all alone for the day :) If I want to generalize my data, I should simplify()? So if the data are in decimal degrees, then is the tolerance decimal degrees? Something like this? CREATE TABLE accipiter AS SELECT gid,engl_name,sci_name,origin,Simplify(the_geom,0.01) as the_geom FROM all_species WHERE family='Accipitridae'; Thanks, Steve