“Well, you could talk about that, couldn't you?”

She nodded; she could not say no. Life in Botswana was a matter of asking and doing. People asked one another to do things and they had to agree. Later they could ask back, and the favour would be repaid. Mma Potokwane understood that rule and never hesitated to ask for favours for the children at the orphan farm, as Mr. J.L.B. Matekoni knew only too well, being regularly called out to fix various pieces of machinery, including the van used to transport the children on outings. And there had been reciprocation in that case, if one counted generous slices of fruit cake as reciprocation; Mma Ramotswe would have called the cake a bribe, given Mr. J.L.B. Matekoni's well-known weakness for such treats, but reciprocation was perhaps a politer word.

Now, just short of the corner that marked the edge of the Sun Hotel gardens, Mma Ramotswe came face-to-face with the woman who had served her tea in Mr. Taylor's office. She hesitated, as did the other woman, who had recognised her too. The traditional greetings were exchanged and then there was a moment of awkward silence. On a flamboyant tree behind a fence, a small, glossy bird watched them, the sun on its purple-black plumage.

The silence was broken by Mma Ramotswe. “I am Precious Ramotswe. I saw you, Mma, in the office at the school. Do you remember?”

The woman seemed pleased to have been remembered. Such people can be invisible to others. “I remember that well, Mma. You were talking to Mr. Taylor. He is a kind man.”

“Yes,” said Mma Ramotswe. “I have heard that.” She paused, searching the woman's expression. Yes, it was there. It was unmistakable. “Do you want to talk to me, Mma?”

The woman gave a start. She was nervous. “To talk, Mma?”

Mma Ramotswe reached out a hand. She did not touch the other woman, but held her hand in such a position that she could take it if she wished. “I think that you are troubled, my sister,” she said. “It is my job to listen to the troubles of others. Did you know that?”

The woman looked down at the ground. She did not take the proffered hand, and Mma Ramotswe let it drop back to her side.

“I know that, Mma. But I am not a rich lady. I do not have money.”

“That does not matter,” said Mma Ramotswe. “I am your sister, Mma.”

It was her way of expressing the old bonds that had always held the country together; a subtle, usually unspoken sense of mutual interest and respect that people could forget about, but that was still there and could be invoked by those who held with the old ways. I am your sister. There was no simpler or more effective way of expressing a whole philosophy of life.

The woman looked up. “It is very good of you, Mma, but I cannot talk now. I have my work to do. I have to get to the school.”

Mma Ramotswe nodded. “Well, as long as you know that I shall listen to you. Do you know where my place is?”

The woman turned and pointed over her shoulder. “It is over on that side. On the Tlokweng Road. Next to a big garage.”

Mma Ramotswe smiled. Tlokweng Road Speedy Motors could hardly be called a big garage, but she knew what the woman meant. When one was down at the bottom of the heap, then any business, even a small one like the garage, could seem big and important.

“Yes,” she said. “It is beside a garage. But it is not a big office, and if you ever come to see me you will be made a cup of red bush tea. You are always making tea for other people; you will have to let us make tea for you for a change.”

The woman smiled at this, and then continued on her way. Mma Ramotswe looked at her watch. There was still plenty of time, but she suspected that walking to work would not be quite as quick as she had imagined.

BY THE TIME she came within sight of Tlokweng Road Speedy Motors and the No. 1 Ladies' Detective Agency, Mma Ramotswe had developed a raging thirst. Her feet, she noted with satisfaction, felt perfectly comfortable-she had her flat shoes to thank for that-and she still had plenty of energy. It was just thirst that troubled her, and that would be easily dealt with when Mma Makutsi put on the kettle for the first cup of tea of the working day.

As she approached the garage, Charlie emerged from the inspection pit, wiping oil off his hands.

“So, Mma Ramotswe,” he called out as she approached. “Has your old van broken down at last? Do you want me to take the boss's truck to fetch it?”

Mma Ramotswe frowned. “There is nothing wrong. I have simply decided to walk to work. It is better to walk, you know.”

Charlie looked at her incredulously. “It is better to walk, you say Mma?”

“Yes, Charlie, that is what I said. And you two could do to walk a bit more.”

“I am always walking, Mma,” said the younger apprentice, who had appeared behind Charlie. “I walk over two kilometres to the bus stop every day.”

“That is very good, Fanwell,” said Mma Ramotswe. “You are not lazy.”

“Nor am I,” interjected Charlie. “I may not walk very much, but why walk if God has given us cars and buses? What's the point?”

Mma Ramotswe took a handkerchief out of her pocket and mopped her brow. “Exercise,” she said. “That's the point.”

Charlie sniggered. “I get a lot of exercise, Mma. I get plenty of exercise by dancing with girls. One, two, three! Like that. That is very good exercise.”

The younger apprentice looked at Charlie with surprise. “Is that true, Charlie?”

“Of course it's not true. Nothing he says is true.” It was the voice of Mma Makutsi, who had appeared in the office doorway, holding out a mug of tea to Mma Ramotswe.

Mma Ramotswe took the mug gratefully. “I am very thirsty, Mma,” she said. “It is kind of you to have this ready for me.”

“If you drove,” said Charlie, “then you wouldn't feel so thirsty. It is too hot to walk.”

“But not too hot to dance?” snapped Mma Makutsi.

Charlie did not reply, but Mma Ramotswe heard him whisper to Fanwell: “Who would dance with her? Nobody. Only that Phuti Radiphuti, and his feet are like elephants' feet. Big dancer. Hot steps.”

Fortunately, Mma Makutsi had gone back into the office and did not hear this remark. Mma Ramotswe gave Charlie a reproachful look. “You should not say things like that, Charlie. It is not kind.”

“She says things about me,” the apprentice replied.

Mma Ramotswe sighed. “You will learn one day, maybe soon, that what others do is never an excuse. Have you not heard of turning the other cheek?”

Charlie was unrepentant. “I have not heard of that.”

Mma Ramotswe began to explain, but could tell that what she said was falling on deaf ears.

“I would never do that,” said Charlie. “It would be very foolish, Mma Ramotswe. You show your other cheek and, whack, they hit you on that one too.”

HE IS HERE NOW,” said Mma Makutsi, peering out of the window. “That is his car.”

Mma Ramotswe made a conscious effort not to look up from her desk. “I take it that it is a Mercedes-Benz, Mma,” she muttered.

Mma Makutsi laughed. “It is a very big one, Mma. It is one of the biggest Mercedes-Benzes that I have ever seen.”

“He is a big man, I hear,” said Mma Ramotswe. “You would never find a man like that driving around in a van like mine.”

Mma Makutsi agreed. She shared Mma Ramotswe's views on cars-that they should be small, faithful, and designed to get one as simply and cheaply as possible from one place to another. When she had a car herself-and Phuti had spoken about getting her one-then she would certainly not ask for a Mercedes-Benz, but would go for one of those small cars that look as if they could as easily go backwards as forwards, so indistinguishable were their fronts and their backs. And she would prefer it to be a modest colour: she had seen a very nice lilac-coloured car the other day that would suit her very well. She had wondered about that. Somebody at the factory had clearly said: Now let us paint this car a suitable colour for a lady. No man would choose lilac, she imagined, and it would be left to a lady to give such a car a home; which she would, and readily so.