Do you have to go through immigration/collect luggage w/a layover in Europe?

Question

If you are flying, say, from NYC to Venice and you have a layover somewhere else in Europe, do you have to go through immigration/customs/collecting luggage at the layover airport or just when you get to Venice? What about on the way back - if I were flying from Venice back to NYC with a European layover? I'm wondering b/c I'm trying to figure out how much time I need to give myself on the layover and obviously it will take substantially longer if I have to collect luggage/do immigration.

Answer 1

i dont know and i live in new york thats mest up

Answer 2

If it is a connecting flight then they are going to go through something like TSA again. However, you will see your baggage only in Venice.