My wife wants a lover. How can I help her find one?

We are a retired couple who have been married for 40 years. I adore my wife and she adores me. We still have an active sex life, but we have talked about her finding another sexual partner to be with on occasion. Neither of us approves of going online to find one. How would you suggest that we find her a “friend with benefits”, whom she can be with and trust? Our kids all live away from us, so we are not terribly hung up about anyone finding out.

The key issue is “trust”. It is never easy to find someone to trust with any aspect of your life – finances, work, household, even grooming – so, naturally, it will be particularly difficult when it comes to creating a sexual triad.

The first thing for you and your wife to do is to discuss in great detail exactly what that “agreement” would look like. For example, would it be OK for the third person to be someone in your community, whom you might see in other settings? Would you risk bringing that person into your home, or would it be better to use a different location? Would your wife see the person alone, or would you be present? What boundaries should be set? What are the safety considerations? Human beings are hardwired to feel jealousy; although you may think this would not arise, it probably would – how would you address that? Would details be shared?

There needs to be clear, transparent, mutual consent – including by the third person. It may be best to seek an established “swingers” community near you, since, within it, you are more likely to find someone who is already comfortable with unorthodox relationships. But you will still have to follow rules, exercise caution and be prepared for unexpected feelings and events.

Pamela Stephenson Connolly is a US-based psychotherapist who specialises in treating sexual disorders.

If you would like advice from Pamela on sexual matters, send us a brief description of your concerns to private.lives@theguardian.com (please don’t send attachments). Each week, Pamela chooses one problem to answer, which will be published online and in print. She regrets that she cannot enter into personal correspondence. Submissions are subject to our terms and conditions: see gu.com/letters-terms.