BTW: Since there is a check against City object being null before the compare method: // TODO: look at what this is doing... if(city != null && other.city != null) return city.getName().compareTo(other.city.getName()); <--- Here happens the NPE if (hashCode() == other.hashCode()) return 0; I suspect the getName()-function from City object to return <null> in some cases. I'm @ work right now and can't explore, but i remember City.getName() checking for Label != <null> but then calling Label.getText(), which does *not* check for <null>. Best regards, Uli -- View this message in context: http://gis.19327.n5.nabble.com/NPE-with-mkgmap-3320-tp5813472p5823349.html Sent from the Mkgmap Development mailing list archive at Nabble.com.