DRIVING TO THE OFFICE in her battered white van, down the Tlokweng Road, past the stand of whispering gum trees, Mma Ramotswe, founder and owner of the No. 1 Ladies’ Detective Agency, allowed her mind to wander. It was easy for your thoughts to drift when you were doing something you did every day—such as driving down the Tlokweng Road, or spooning tea into the teapot while you waited for the kettle to boil, or standing in your garden looking up at the wide sky of Botswana. These were all activities that did not require total and undivided concentration, although her husband, that great garagiste, Mr. J.L.B. Matekoni, stressed that driving demanded your whole attention. Mma Ramotswe, though, felt it was perfectly possible to drive carefully and yet at the same time let the mind wander. There was not a driver in the country, she imagined, who did not think of other things while driving—unless of course there were, somewhere or other, people who had nothing at all to think about.

That morning she thought of what she would cook for dinner. She thought of letters she might receive and of the replies she should write. She thought of how she knew this road so well that she could drive it blindfold if necessary, and still get to her destination unscathed, or largely unscathed. She thought of how month by month, year by year, the traffic had got worse, as traffic always seemed to do. Was there nowhere on this earth where traffic got better; where the lines of cars thinned; where one could park virtually anywhere, as one could in the old days? And she thought of the people in her life, the people she would see that day, and the people she would not.

The people in her life…These, she felt, were of two sorts. Whatever further classifications might suggest themselves, at the outset people could be divided into those who were late and those who were still with us. The ranks of the late were legion, but each of us had a small number of late people who meant something special to us and whom we would always remember. She had never known her mother, who had died when she was still an infant, but her father, Obed Ramotswe, she had known well and still missed as much as ever. Every day she thought of him, of his kindness and his wisdom, of his ability to judge cattle—and men—with such a perceptive eye; of the love he had borne for her and of how his passing had been like the putting out of the sun itself.