One on One… with William Davies

I'll start with the easiest of the questions you sent: One treasured possession. This is my Omega watch which my father bought me because he was so pleased with my elder brother getting into Barts medical school. My father was a pharmacist, so his boy going to Barts was a great thing… so great that he bought him a nice Omega to go up to London with. I think he sensed he would never be so proud of me but his spirit of fairness dictated that I should have exactly the same as my brother, so he bought one for me while he was in the moment. Never mind, it's a great watch, but I wonder if my brother ever ponders whether if dad hadn't had to buy two of them, then he might have got a Rolex? Who knows.

Onto the most difficult one: one moment that changed the course of your career. Easy to answer, but not quite so much fun as my Omega. I was going to read engineering, but when I was 17 I was involved in an event that was both traumatic and tragic, and when I got out of hospital the appeal of wonderful suspension bridges, gas turbine engines, and other engineering miracles seemed completely to have disappeared. So, instead of going to Cambridge to read engineering, I went to UCL and read psychology. In the hope that it would prove helpful I suppose, and it did.

There is a natural lead on to 'One hero from psychology past or present'. There are several, but as I'm just allowed one, I'll gladly choose Prof George Drew at UCL when I went up as a student there. He had got all the boxes ticked: he made Psychology fascinating, he was a terrific lecturer (he had a great habit of giving us lots of academic knowledge about a topic, then illustrating it with a really good relevant anecdote), but above all he was a very nice man. And he sensed I needed a bit of looking after, so he did just that, and when I repaid him by going off and becoming a trainee bank manager, took no offence when I returned – two days into my training – to ask his advice. Rather he phoned up his friend who headed up the psychology service in HM Prisons and got me a place on the selection procedure to become a prison psychologist. Something which really turned things around for me. I can't believe I can't find anything about Prof Drew on Wikipedia, and there is precious little on Google. An amazing man.

One person who inspired you. This is an easy one too. The first prison psychologists' conference I went to had a number of people standing up delivering papers, of whom Derek Perkins was one. I thought how I would really like to be like him and maybe if I tried very hard, could be. I'm still trying. Never mind, in the interim, in 1981, Derek and I founded the Association for Psychological Therapies, reasoning that it would be good to make post qualification training more professional and organised than it then was. He left formal involvement with APT after a couple of years, but he made an indelible mark in that time.

One example of the effects of hyperarousal on thought. Being interviewed to get on the Birmingham clinical training course. I really wanted to succeed, and the interviewer was encouraging, he gently asked if I had time to read in my job as a prison psychologist. "Oh Yes," I said, thinking of the novel I was reading at the time. "What psychology books are you reading at the moment?" he asked. Such is the effect of hyperarousal that I couldn't think of a psychology book I had ever read, let alone at that moment. Still, it turned out alright. Maybe they saw the funny side.

One proud moment. I think this is a great question. I can never quite understand it when people are given an award or have just made some achievement, they say they feel incredibly 'humble'. I think 'proud' is the word they really mean, so, good question. One very proud moment was when my colleagues and I calculated that over 100,000 people had received training from the Association for Psychological Therapies. Each person in a small group of 12 or so, over a period of typically three days. So a hundred thousand people is a lot. We've gone way past that now, but somehow or other, the 100,000 mark was the one that hit us, and still the one we quote.

One aspect of leadership. Some of my colleagues at work secretly (that is, without telling me, and working in their own time) sent in an application for the Investors in People 'Leader of the Year' award. They did it secretly because they didn't want me to be disappointed if nothing came of it. Ridiculous, because the fact that they nominated me for such an award was good enough for me. But, it turned out even better, because I'm on a shortlist of four, so as far as I'm concerned that's a result. So to choose just one thing about leadership is really tricky because there are lots, aren't there? But maybe the main one is to really like everybody in your team, not just because that oils the wheels, but because it means that you try to get everybody in a role that thoroughly suits their talents, and if you can do that the end result is amazing: everybody knows they are doing their job better than anyone else could, and everybody looks around in wonder at what others can do.

One cultural recommendation. This one made me smile because my wife has a Masters degree in art history, so I've long since got used to keeping quiet about any cultural notions I might have. Even so, if ever you get a chance to see Went the Day Well? I think you might find it interesting. It appears to be a nostalgic black-and-white movie about an English village that gets taken over by German troops during the Second World War. And how the plucky English villagers thwart them and get help, and all turns out well. What makes it astonishing is that it was actually made during the early stages of the Second World War, not after it, and at the time of its making things were not going at all well for Britain. So it is a triumph of optimism and the ability to project yourself forward in time, because it is recounted as though the year is 1950 or thereabouts. And the icing on the cake is that it was made by the Post Office. No, actually, there's another bit of icing on the cake – or candles maybe – namely that I used to think my liking for this film was just some strange peccadillo I had, but it turns out that it is a really classic film.

One thing about working with challenging behaviour. Don't focus any more than you have to about the challenging behaviour, focus as much as you can on nurturing the positive behaviour and helping the person live an enjoyable life.

One thing about irritability. Check you've done all you can about any depression, anxiety or PTSD.  Being happy and relaxed (or at least active and not too anxious) is a great start to not being irritable.

One book that all psychologists should read. I really enjoy reading Irving Yalom's accounts of his patients, and maybe his best book is Love's Executioner. And when I realised that his office was in Russian Hill (San Francisco), one of the top spots in the world, I emailed him to see if I could go over and have a therapy session. And so I did, and that was my first and last therapy session, but that was amazing too; maybe that's 'one thing that every psychologist should do'.

One thing that makes me laugh. Generally, comedies don't make me laugh, but there is an exception: Modern Family. How do they think of that script?

Just one final thought – a psychology undergrad was asking me recently about the merits of becoming a clinical psychologist, and I found myself saying that if I was faced with the same questions again I would want to decide exactly the same as I decided first time. So maybe even very dark clouds have a silver lining: in my case the silver lining was moving into psychology and I'm very glad that happened.

- William Davies is the chief executive of the Association for Psychological Therapies, author of Overcoming Anger and Irritability, and author of the RAID® Course for working with challenging behaviour.