For, towards, as for: đối với

Đối với means "for" in the sense of "as far as … is concerned". At the start of a sentence, it names whose view you're giving: Đối với tôi, gia đình quan trọng nhất. For me, family comes first. It can also bring in what you're about to talk about: Đối với trẻ em, vé vào cửa miễn phí. For children, entry is free.

After an adjective, it says who something is that way for: Món này hơi cay đối với người nước ngoài. This dish is a bit spicy for foreigners. It also follows words for how you treat someone: tốt đối với nhân viên, good to the staff.

In conversation, với alone often does the job: Với tôi, …, hơi cay với người nước ngoài. Đối với sounds more careful, and it's the usual form in writing, speeches and the news.

It's never the "for" of a favour or a gift. For the person who gets something, or for whom you do something, use cho: Tôi mua quà cho mẹ.