Traveling as a dual national

A question for those of you with dual nationality, particularly those on longer journeys: do you travel with both passports? Has anyone come across or heard of any problems that might arise? Thanks!

I'm a dual citizen (USA and Hungary) and have traveled with both. It's mainly great because I can stay in Europe as long as I want and don't have to pay outrageous visa fees in some countries (mainly South America for the USA one, but need lots more visas in Asia and Africa for the Hungarian one). If all things are equal then you can always just go in whichever line seems shorter for customs too.

The only thing you have to remember is to be sure to use the same passport to leave a country that you used to enter it, especially if they swipe the passport when you enter. That and for the USA at least you're required to always enter the country on your US passport if you have US citizenship, I don't know how many other countries have that requirement for their own nationals.

I always carry both (US and Netherlands) and I've never had a problem. I find it to be an advantage - you can choose which one you want to use to get you in the shorter line, or to get the cheaper visa The only thing that's problematic is trying to switch passports if you're visiting multiple countries overland. I entered Peru on an American passport, then tried to enter Chile on my Dutch passport, but the immigration official wouldn't let me. Said the stamps needed to be all in the same passport

My partner also has two, US and UK, and she uses whichever one has the cheaper visa prices. Also, using her UK pp to visit her family so she doesn't have time restrictions.

Wish I had 2 passports...

Thanks, all, VERY much appreciate the input.