Alot of good thoughts on both sides here. My friend has a lovely intact (house trained) affenpinscher who came for play day and proceeded to mark inside my house as soon as he arrived. She was mortified, but apparently that is not uncommon when intact males go a visiting. I guess that is their special way of saying hello. Anyway, the humping and marking is starting to annoy everyone so she has made the appointment for his big snip in a few weeks. Just something to think about on top of all the other truly valid reasons to neuter. If not, make sure you invest in a couple of good belly bands when out and about.