When Ernest Hemingway was asked how you could know whether you could trust someone, he growled: ‘Trust ‘em’, before banging his empty glass on the El Floridita bar, trusting that the barman would give him another daiquiri as perfect as the last.

At least, that’s how I imagine it: a casual but typically succinct and challenging response; a brush-off to send a would-be worshipper on his way.

Not that it’s not good advice. I have followed it myself – albeit with mixed results. An unpromising tenant (on paper) has turned into a lifelong friend. But another ‘trust him’ punt ended in one of my flats being turned into a cannabis factory. Embarrassing and costly, but not the end of the world, and on balance, trusting the Hemingway precept has served me well.

But I wouldn’t trust it in more serious scenarios. Take a rope. Would anyone just trust it to take their weight, or would they test it in some way before throwing it over the edge of the cliff and climbing down it? When it’s a matter of life, I imagine we’re all rather more circumspect.

And this is at the heart of the relationship between the ghostwriter and the client who is indeed trusting them with his or her life. If it’s going to work, it has to reach levels of intimacy normally associated with therapy. Interviews will need to go deep to get at the full story, and this may mean uncomfortable questions. But the hope is it will make for a much better book – and, again, hopefully, prove therapeutic.

Once trust is established, the levels of candour can be surprising. Ghosts can find themselves entrusted with secrets that would come as a shock to close family members, let alone the wider circle of friends and colleagues. Obviously nearer the end of the project, the question of how much sensitive material really needs to see the light of day comes into focus. And all responsible ghostwriters will warn of the dangers of being sued for libel. It’s not necessarily true that all publicity is good publicity.

Of course, trust is a two-way street. Which is why the initial telephone conversation is so important. The client needs to feel that his or her life will be in safe hands; and the ghost has to assess whether the relationship is going to work. While we will bend over backwards to realise the vision of the proposed book, everyone has experienced clients who prove difficult to satisfy, change their mind about the direction of travel, and in some instances simply disappear like mountain goats into the mist.  (I still have on file a contract signed by a client with whom I spent hours on the phone. I’m still waiting for the initial payment. Suing for breach of contract is not a great start for a ghostwriting collaboration.)

But to end on an optimistic note. Only last week I got a call from a friend of a friend who recently lost his father through motor neurone disease. A heartbreaking story, especially as the diagnosis came late, meaning his dad was still working long after he should have stopped. His son had kept a diary of his painful decline. Could it be turned into a book?

Send a sample, I replied, and a little while later I responded in a text saying Yes it could be turned into a book and that I was happy to help with the process. The writing was direct, uncomplicated, and the narrative thread straightforward. The old English teacher in me felt for my red biro, but it won’t need much more than a light edit. I’m not charging for this little service (the original friend has bought me too many beers over the years); it’s a good project and will certainly be some help to those who find themselves in the same crushing predicament.

And the book I am just about to start writing came about through another phone conversation. This one was initiated by me in response to a request for guidance by a potential client to United Ghostwriters. It didn’t seem promising, but as there was a phone number, I thought I’d report the bad news in person.

Half an hour later, things had changed. The author is quite a personality and I started to see ways in which a rather unorthodox book could satisfy his desire for a memoir as well as find a potential audience.

I wrote a chapter synopsis and a pitch and sent it to a specialist agent, who turned it down. I then sent it to my own publisher, just to get his opinion, and he phoned back within an hour saying he’d like to publish it. Contract in the post!

It doesn’t often happen like that, but the importance of that first telephone conversation cannot be emphasised enough.

Make that call. You’ve got nothing to lose.

Trust me!