For most marriages, sex is a very important ingredient. A healthy, mutually satisfying sex life can enhance intimacy and passion and provide an important buffer against the inevitable strains and stresses of marriage. An unsatisfying sex life can both cause difficulties in a marriage and be a symptom of relationship problems. It is important to note, however, that not all couples require the same degree of sexual activity. Moreover, sexual activity tends to decrease as couples age. What is important is that the sexual relationship works for both members of the couple.