Sex File: He doesn't kiss me properly anymore — how can we resolve this?

Research by Susan Hughes at Albright College in Pennsylvania suggests that men are more likely to initiate kissing before sex, when it might be used for arousal purposes, whereas women are more likely to initiate kissing after sex, where it might better serve a relationship maintenance function.

My partner of five years never kisses me properly any more, unless it's definitely going to lead to sex. I know we're out of the honeymoon period but I miss the kissing sessions we used to have as a pleasure in their own right. How can we resolve this?

Kissing is greatly underrated but there has been a lot of research into it. Most of it concludes that kissing is a fundamental measure of relationship quality and, having read a number of papers on the subject myself, I believe that none of us are doing enough of it.