Management question

You are the HR Director for a large manufacturing organization that supports the auto industry. You have over 500 employees. You have gotten word that they are threatening to organize. Your management team is wanting you to put a presentation to them to get them up to speed about what they are facing and what can be done. Explain the reasons why employees form and join unions. What if anything can management do to convince the workforce to not unionize? What could management have done and what should they do in the future as far as being proactive in managing a union-free environment.