Rodney, 53, gas engineer

My schooldays in Hong Kong really were the happiest of my life. I have rarely felt the same sublime happiness since. Doesn't that sound awful? I was good at sport and loved to win. I broke school records, won medals. I particularly remember one 400-metre relay. I was running third. We were up against all the other schools in the colony. When I took the baton I was a few metres behind. I ran like the wind and got ahead, to give the anchor man the best possible chance. Our team came first, and when I went up to collect my medal, I was given a standing ovation. I almost burst with pride.

Nowadays, I am broadly content, but I rarely have the same highs. In my twenties I felt deeply stirred by my first sight of the Grand Canyon. I just stood there for ages enjoying this exquisite sense of pure joy. It was almost like being drunk.

Rhiannon, 22, student

In my first few days at Keble College, Oxford I felt ecstatic because I was independent for the first time and socially it was very hectic. I had been aiming to go to Oxford for so long, it was a relief.

Rose, aged five

It was with Daddy when we went to Aunt Cordelia's and picked some corn, and Daddy put some pigeon feathers in my hair and it made me feel better. And when I was in the swimming pool with my brother it was freezing and I had fun in the deep end.

Julia, 47, teacher

My mood has so much to do with the weather. A beautiful, sparkling day makes my spirit soar. I get a great surge of well-being. Then going on holiday, driving up to the port, knowing we're off, I get the same butterflies of excitement I got as a child. I know of nothing like it. The kindness of strangers can be very moving. The Algerians in France who came out and tried to help us when the car broke down, the man in Brindisi who changed my inner-tube for 2,000 lire ... people like these make you feel a bit more hopeful about being human.

Rachel, 39, legal secretary

My husband had been ill for several months with one of those mystery viruses that so many people seem to get these days. He was very weak, and there were times when life seemed hopeless. Some nights I lay there listening to him breathing, thinking he would never be well, that our quality of life would be minimal - at worst, that he was going to die.

I became terribly sentimental, I could be moved to tears by the slightest thing, and not just to tears of misery. A few times I was brimming over with what felt like happiness. It was all rainbows on roses and whiskers on kittens sort of thing. I would be looking at the world with new eyes, thinking how wonderful it was to be alive.

Then, when my husband began to get better, I would be momentarily beside myself with joy. I came as close as I have ever done to believing in a benign God. I have always been avowedly atheist, but I had a fleeting sense that there was a purpose to all this. It seemed to me similar to the experience people speak of when they have died and been resuscitated. I had seen a kind of metaphorical light.

Yvette, 18, student

When I eventually passed my practical driving test last month, I was overjoyed, and then I passed the theory a week later. It felt as if I had been learning for ever, and I was delighted.

Colin, 32, accounts manager

Waking up in the morning with a clear head, after 14 years of heavy drinking, has made me feel renewed. I gave up alcohol nearly six months ago, and I have a tremendous sense of achievement. Nothing I have ever done can compare with it. I am glorying in my sense of pride and power.

Roy, 67, retired chauffeur

When I first saw my new granddaughter, I felt the purest love. I didn't see very much of my own children when they were growing up, and I regret that now, because I can watch Sara and see what I missed. I suppose I was always so busy working. The idea of retirement and enforced idleness horrified me. Yet I would say I am as happy now as I have ever been.

Tom, 'nearly 12'

Uhm, I can't think when I last felt that. Just before I go on holiday I always feel happy. Or if I've got something I've really wanted for a long time. Probably the last time I felt really, really happy was when I was allowed to take some money out of my bank account to buy a skateboard. I felt great when I got the board. It was expensive but worth it. Also, I went on a tennis course last week and I got three Wilson tennis balls for being overall winner. I felt very pleased about that.