Alerts based on Priority or by user (couple questions)

Hello

I'm wondering if it's possible to have email/text alerts based on the Priority Level of the ticket request. . Also is it possible to have alerts based on the user (high level executives) that submits a ticket?

Along the same lines, I'm wondering how to handle a secretary submitting a ticket "on behalf of" an executive. I doubt our executives will take the time to submit a request, but we will want their secretaries to do it. But the owner of the ticket will get the updates and not the person whom the work is requested for. How do other people handle this situation? Can updates be sent to more than just the owner?

thanks in advance.