Masters of Public Health. Mostly looking at American top 10 programs, but looking a little in Europe too. I have a few friends who came to the US for undergrad and it's worked well for them. I need to look into how well a European program would translate back here as I will probably stay in the US long term, but I wouldn't be opposed to moving to Europe permanently should the right opportunity arise.
A friend of mine did MPH. Ended up being in charge of school nutrition for like Los Angeles. He did it for a good long while (I feel like five-ten years) and then did law as night school because he hit a ceiling as far as what he could do policy-wise. Definitely keep your eyes open and look for people doing the stuff you wish you could do - then ask them how they got there. There's an awful lot more who-knows-who in public policy work than you might think.