We were reminded yesterday of just how important the social standing of godparents is when it was revealed that Princess Diana had 17 godchildren, and that they would benefit from her will.
The late princess may well have been asked to appear beside the christening font because of her spiritual values, but the cachet of having the most famous woman in the world as a kindly benefactor for your child would have been substantial.
Picking famous godparents is like a subtle form of name-dropping. I know of people whose godparently roster for their children includes the designer Paul Smith and the actress Anna Massey.
An example is a friend of mine, who happens to be married to a rather well-known designer. "I've been asked to be godmother to someone's daughter. I know it's only because of my husband," she fumed. "The mother thinks this means her daughter will get artistic presents and career introductions at every opportunity. I've reluctantly agreed, but I'm damned if my husband is going to have anything to do with it."
In some circles, godparenting is now a sort of social skill worth boasting about. "Oh God, my friends just collect godchildren like little trophies," says society animal painter Delia Marr, whom Tatler has acclaimed "Britain's foremost dog artist". "I know one woman who goes around saying things like 'Lucky me, I've got 20!' It's just ghastly. It's a sort of social thing, you see. Lets people know how popular they are. And people take on far too many."
Not that Ms Marr, whose clients include the pets of Roger Vadim and Anouska Hempel, was herself above reaching for social grandeur when her own daughter's baptism came around. "It was hopeless. We asked a German countess to be our daughter Emily's godmother. She gave Emily a marvellous christening dress, and since then, nothing. Dead loss. I always say no, if asked myself. I don't want to be a godparent. It's enough work being a real parent. It's a pain and it has lost all its proper meaning. It's become a Christmas and birthday present thing. And you can't just hand out fivers to children these days. They expect more than that, at least pounds 30. Do you know, I think I'd rather be a godparent to a dog than a child."
Godparents are a cornerstone of social structure, according to Drusilla Beyfus, author of Modern Manners, and herself parent to several god-offspring. "I can't say I'd pick a celebrity for a godparent. Frankly, he or she won't be the slightest bit concerned about your child. They're too busy being famous. A good godparent must be interested in the child concerned".
According to Ms Beyfus, the vogue these days is to have at least four "fun" and interested godparents, selected from a sort of denominational bran-tub, "One Greek Orthodox, one Jewish, and so on. At least one of them should live abroad."
The Rev Peter Bishop, chaplain of St Clement Danes in Fleet Street, who does the business at about 30 christenings a year, says that an increasing number of godparents are keen on having a canonical chat before the big day. "Whether they are baptised or not is not of great significance to me, although legally I know they should be. What is more important is some sense of spiritual idealism."
However, even if you are morally and socially acceptable you still have to be prepared to muck along with your godchild. A famous and reasonably well-off inventor might well be a good choice. Perfect for those exciting Christmas presents. "Oh God no," says Sir Clive Sinclair. "I was once asked and I said I can't, I'm an atheist. Actually I think I did have a couple, once, but I can't say I looked after them. Sort of lost them, or forgot about them."
Rosie Millard is the BBC's arts correspondent. Her daughter is being christened tomorrow and the godparents include a TV director, and a media lawyer with his own plane.