There is a general assumption that any interference with sex in marriage will harm the relationship of the couple, and therefore sex must always be available to the couple without any restraints, if the relationship is to be kept going. Yet, the much acclaimed ‘sexual revolution ‘in the west, with its sexual freedom, has not led to a growth in marriage stability. The world at large and the majority of married couples are totally ignorant of the WHY and HOW of Natural Family Planning. This book helps to remove this unfortunate lack of information by bringing out competently and in some detail as to why NFP has the surprising benefit of enriching the marital relationship and how it promotes happier and more permanent marriages.