NO - MUNGO DENISON, CELEBRITY LIAISON MANAGER, THE CHILDREN'S SOCIETY
An individual's support for a charity should be an organic relationship.
Celebrity support is no different. They are themselves volunteering and, although Osbourne's suggestion is interesting, introducing a contract would undermine this relationship.
It's too prescriptive and would be fraught with legal and logistical issues. A number of celebrities lend their support to more than one charity.
That should always be their right, and contracts would muddy this situation.
At the Children's Society we have found it works best to discuss and agree levels of support on an individual basis with a celebrity supporter without the need for contracts.
With regard to appearances, no contract would or should prevent a celebrity from turning down the 'Hollywood offer', so it would therefore be unable to offer protection against the very thing it was introduced to protect.
In a climate where the appetite for celebrity is ravenous, the manner in which these relationships are managed has had to change. But introducing contracts would present more problems than it would solve.
YES - PEDRO CARVALHO, FOUNDER OF FNIK PR
Sometimes celebrities don't turn up or they can do something that is potentially damaging to their reputation and the reputation of the charity.
A charity's image is important, so there has to be a get-out clause.
I used to work with a big children's charity that could only call some of its so-called celebrity supporters once a year, and even then some of them would say no. A contract would ensure celebrities turned up to an agreed number of events and couldn't simply say they were too busy.
Celebrities can be volatile and flaky. We have had a nightmare recently with one that turned up to a charity event and was obnoxious and made a scene. Of course, not all of them are like that, but a high percentage are.
A diabetes charity approached me recently because it wanted my client, the Radio 1 DJ Nihal, to support one of its campaigns. His mother has diabetes, so it's an issue close to his heart.
But quite often there's no link between the celebrity and the charity's cause.
For the relationship to work, the celebrity has to be committed and has to care. If they care, they will not mind signing a contract.
NO - MOLLY BEDINGFIELD, FOUNDER AND CHAIR, GLOBAL ANGELS
Having a celebrity involved is more of a privilege than a charity's right.
When we are lucky enough to have the involvement of one or more celebrities, our relationship is more of a friendship than anything else.
Music artists and celebrities have any number of demands on them at any one time and when they fit helping us into their schedule, we understand the extra effort this takes and are appreciative of them for that.
I really don't think that treating celebrities as corporates and having contracts would benefit either party. In fact, it's more likely to steer the relationship towards a business relationship than a privileged partnership.
We treat celebrities the way we would treat any person who wants to help us - as friends.
We see an increasing number of people who prefer the personal approach to the things they do, and that's really the whole ethos of how Global Angels works as a charity - we strongly believe that this is the best way forward.
NO - DOMINIC NUTT, EMERGENCIES SPECIALIST, CHRISTIAN AID
Christian Aid does not ask celebrities to sign contracts. It would be entirely counterproductive. A contract is a legally binding document that applies sanctions to either side if they break the agreement. But what would our sanction be against a celebrity who we weren't paying and on whose goodwill we were relying?
Would we really want to take them to court? The bad publicity we would attract by sueing a volunteer would far outweigh any benefits we might gain from working with them in the first place.
And what would other celebrities think, knowing that once we had signed them up, they could be trapped by their commitments to us and therefore have to turn down paid work in the future because they were meant to be engaged with us?
We are building long-term relationships with our celebrity ambassadors and they need to feel confident that we understand that they have other commitments. And we want them to work as actors, pop stars and TV personalities because that is what makes them attractive to us in the first place.
So we have to take it on the chin if celebrities cannot always be available to us when we would like.