Doris Lessing’s novel The Diary of a Good Neighbor is very meaningful in that it spotlights an older woman over ninety, Maudie Fowler. The heroine and successful career woman, Jane Somers, happens to meet Maudie, becomes her friend, and finally completes a journey of self-discovery. In Barbara Frey Waxman’s terminology, this work belongs to the genre of Reifungsroman, as it is a novel of ripening maturity, focusing on a middle-aged heroine’s spiritual growth. But this paper highlights the life of Maudie who represents “older women,” an expression that emphasizes not the distinction, but the relationship between different age groups, in comparison with that of “old women.” Showing the poor life of Maudie, Lessing insists that family, society, and social welfare systems should cooperate to take care of older women. Furthermore, she believes that society should treat other minority groups, such as immigrants and low-waged female workers, including social welfare workers and nurses, without discrimination. Lessing also connects Jane’s experience of having taken care of Maudie with the nurturing of her sister’s difficult teenage daughter, which is one of main themes of Lessing’s next work, If the Old Could . . . . Through these two novels, Lessing suggests that we should see old age in terms of intergenerational relations, and consider the relationship between the young and the old not as a binary opposition but as part of a bigger picture and a continuum of a reciprocal relationship.