There should be a box above responses within a need to type in a name and click add. The same as you would add the need to a user group, we should be able to add users to needs without assuming their identity and then having to sign out and back in. When there are larger groups, this becomes an impossibly long endeavor.

I know this suggestion was made a while ago but I also think it would be helpful to have a way to assign volunteers from the opportunity page rather than going to the responses page. If this has changed over the last several months let me know - I did have a hard time figuring out how to assign people to an opportunity until I went back through the training - it isn't one of those intuitive things, as I find most of the other features on the site to be.