One of the best things about being a journalist (a loose term that includes louche once-a-week columnists) is that you can phone complete strangers and say to them: "Hello, I'm so and so and I would very much like to interview you."

Often the person you want to interview becomes extremely suspicious, not infrequently paranoid.

A phone call from a journalist sometimes sets alarm bells ringing and necessitates the deployment of media relations experts (most of whom know very little about relating to the media), even lawyers.

Occasionally, however, you come across someone important who says: "No problem. What would you like to discuss?"

These are usually people who have had many dealings with the media and understand that we hacks are not the demonic troublemakers we are sometimes made out to be.

Recently, after reading The Cheetahs of De Wildt, I got it into my head that I would very much like to meet and interview the author, South Africa's "Cheetah Lady".

So I phoned and got put through to the great lady herself.

She listened to me and said: "What about Thursday at 2pm?"

And so, on Thursday at 2pm I duly presented myself at the Ann van Dyk Cheetah Centre near Brits. I was warmly received by a legend of conservation, a woman who has worked to preserve these most beautiful of all animals for more than 40 years.

Cheetahs really are the most gorgeous creatures on the planet. They are the super models of the animal kingdom: lithe, beautiful and terribly sexy. Next to cheetahs, lions are the AWB of the bush; big fat overrated bullies. But livestock farmers hate cheetahs and shoot them at the drop of a hat and so we're fast running out of the cats. There are only some 2000 wild ones in the whole of South Africa.

Just imagine how future generations would revile us if, on our watch, we allowed cheetahs to go the way of the dodo. Fortunately we have people like Van Dyk working tirelessly to ward off the very real threat of cheetah extinction.

At De Wildt, Van Dyk and her team protect, propagate and patch up cheetahs and wild dogs. At any one time there are 60 or 70 or so cheetahs there, plus a similar number of wild dogs. De Wildt has also worked wonders with caracals, various antelopes, honey badgers, vultures, riverine rabbits and Anatolian guard dogs (Turkish hounds that are so clever and so devoted to their charges that they will confront and see off predators, including cheetahs.

Since the National Zoological Gardens cut De Wildt loose more than a decade ago, Van Dyk has had to live by her wits to keep De Wildt going. It's a small business, and one that has constantly got to look to the bottom line.

These days De Wildt keeps going by offering tours and through corporate sponsorships, supplemented by the sale of captive-bred cheetahs or wild dogs to overseas zoos.

The education department is a registered non-profit company, with a Section 18A - sponsors can claim credits for money they put towards the education programme.

Thousands of pupils are exposed to the cats and other beasties either by touring the facility or by visits to their schools from one of the education staff, accompanied by a real, live grown-up "ambassador" cheetah. A great deal of the outreach work with children, exposing youngsters to De Wildt's conservation messages, is to historically disadvantaged schools that cannot afford the modest fee usually charged per pupil.

I was too shy to ask Van Dyk about the nitty-gritty details of the business that is De Wildt; things like turnover and operating costs.

These might keep her awake at night, but for those outside of the operation they are of little consequence when measured against the sustainable value created by saving a magnificent animal from extinction and in turning young minds on to the importance of conservation.

• Surprisingly, for someone who has spent most of her life working with cheetahs, Van Dyk doesn't know everything about them: she expressed no firm opinions when I asked her about the advisability of picking captain and hooker Adriaan Strauss for the Springboks.