ElementAPI: Include author/user data with entry?
$entry-&gt;author is going to be a UserModel object, so you've got access to all of its properties and methods depending on what you need to return.

i.e. $entry-&gt;author-&gt;firstName, $entry-&gt;author-&gt;lastName, etc.

Here's a list of them from a Twig perspective, but the same things are available to PHP. https://craftcms.com/docs/templating/usermodel