Some years ago I wanted to write a scene in which two teenagers were having their first date. The girl was epileptic and as a consequence her parents were over-protective. She hadn't told them about this date and she was Worried that she might be seen by someone she knew. She was also worried about what the boy would think of her, worried that she wouldn't know what to say to him, worried that if he found out she was epileptic he would be horrified, and worried that she might have a seizure right there in the café.
So there was plenty to focus on. Nevertheless, when I read the scene through it seemed insubstantial. I realised that there was hardly any Setting. I'd based the venue on the Haagen Dazs café in London's Leicester Square. So I decided to make a special trip there, for research purposes you understand, not just to pig out on ice cream.
The place was crowded when I arrived and I took the only free seat. To my left was a very smartly dressed young Asian couple and they were snogging. Actually, snogging is not a strong enough word for what they were doing. Utterly oblivious to their surroundings, they were practically eating each other.
On my right, were two Young Arab Women wearing burkahs. One of them had a shoe box full of home-made flash cards with Arabic words written on them. One by one she was taking the cards out of the box and showing them to her companion who was frowning earnestly as she struggled to pronounce them correctly.
In the twenty minutes I was there a whole procession of characters came in off the street - glowering Goths, noisy tourists, harassed looking parents with over-excited children, even a couple of police officers with a weakness for whipped cream and macadamia nuts.
When I went home and rewrote the scene I put in everything I had seen and this time, of course, there was far too much detail. I had to strip a lot of it out at the next draft but I kept the Asian snoggers and the two young Arab Women because they were a gift and because I could never have made them up.
So that's what I've been trying to tell my students. Setting isn't just architecture; it's everything that's going on around your characters.