A model was developed and a static game of complete information was applied in an examination of a married couple’s reciprocal relationship. Each chose best strategies (i.e., optimal responses) to maximize payoffs (i.e., happiness). Theoretical analysis suggests that the couple’s happiness is endogenously and positively correlated and simultaneously determined. If the wife (or the husband) is not happy with the relationship, it is impossible for the husband (or the wife) to be happy with the relationship.