Secondary Template for Structure I created a Profile structure for my client's employees. He asked if I could generate an email signature for them from their Profile. I figured out a way to put all the signatures on one page using a

{% for entry in craft.entries.section('profiles') %}


loop on a single page.

However, is there a way to give each person their own page for an email signature? /PROFILE/email-signature that pulls content from the profile. I want this to update dynamically as he adds/removes employees.

How would I create a secondary template for the profiles for an email-signature?
It sounds like you need to create a dynamic route by going to Settings > Routes > "New Route".  Then you'd set your custom route to profiles/{slug}/email-signature and decide which template to serve when the url looks that way.  

You can either serve the _entry template you're serving for /profiles/john-doe or create a new one. Depending on the situation, you may need to set the entry in the template like...

{% set person = craft.request.getSegment(2) %}
{% set entry = craft.entries.section('profiles').slug(person).first %}


...in the event Craft can't figure it out because you're on a separate template.  Grabbing segment 2 means you're grabbing john-doe from the URL, which will help Craft know which entry to find.

Here's more info on routing in the docs: https://craftcms.com/docs/routing#dynamic-routes