How do I introduce the idea of having an open marriage?

Why do you want to have an open marriage? I had a friend who had an open long term relationship and it ended in disaster for them. They are not together anymore. If you really want to have an open marriage i suggest watching movies or tv shows together like big love and then start a convo after the show and gauge your spouses reaction to it.

Ermmm do you mean open marriage as in a swinging marriage where you guys are open to the idea of seeing other people or do you simply mean open as in open with your thoughts and views about everything. Your question seems a bit ambiguous and misleading...