Many believe that between is appropriate when there are two people or things involved, and among is appropriate when there are more than two people or things involved. While this might give you the right answer some of the time, it isn’t strickly correct and you could end up creating awkward feeling sentences like:
Tensions among Canada, Mexico, and the United States eased following the implementation of the NAFTA agreement.
The reason this may feel awkward is because it’s wrong. The correct sentence is:
Tensions between Canada, Mexico, and the United States eased following the implementation of the NAFTA agreement.
Here’s why.
Between is the word to use when talking about distinct, individual items, even if there are more than two of them. The Chicago Manual of Style (CMS) calls this a one-to-one relationship and acknowledges statements like trade between members of the European Union to be correct.
Among is the word to use when talking about things that aren’t distinct items or individuals; or as CMS call it, undefined or collective relationships. That means honour among thieves is correct.
But wait, there’s more.
Between is also the word to use when describing a location relative to two distinct people or things. So when I write “I walked between the trees,” I am giving the idea that I stayed between to specific trees or that I walked on a path the was surrounded on either side by trees.
Among is the word to use when describing a location inside a general or collective group. Writing “I walked among the trees” implies I wandered in the forest, not on a specific path.
And then there’s amid, amidst, and amongst. Amid is the word to use with mass nouns; “amid talk of war”, “amid controversy.” And most modern style guides discourage the use ofamongst or amidst.
