Chapman recalls a conversation he had years ago on an airplane. A man asked him, “What happens to the love after you get married?” (11). The man recounted his several failed marriages, leading Chapman to reflect on failed relationships. He asked himself, “why is it that so few couples seem to have found the secret to keeping love alive after the wedding?” (14). His answer provides the key and foundation to the book: “The problem is that we have overlooked one fundamental truth: People speak different love languages” (14). Chapman says that the root of the problem lies in the arena of communication and that we must learn to speak our partner’s love language fluently.

Chapman notes that love is “essential to our emotional health” (20). He uses a metaphor that will reappear throughout the book: “Inside every child is an ‘emotional tank’ waiting to be filled with love […] Much of the misbehavior of children is motivated by the cravings of an empty ‘love tank’” (20). While initially used in reference to emotional development in children, the existence of the “emotional tank” continues throughout our adult lives.