Three years ago, I wasn't an activist. I was in Madrid, living the sybaritic, unbearably light existence of an English teacher. Since my students at J.P. Morgan Bank were defiantly proud of speaking only Spanish, I had constant employment, teaching them sex vocabulary and variations of the same grammatical lesson over and over, which they duly forgot. I'd been doing this for three years, as had my expatriate friends, and all of us lived in a drowsy limbo, immune to time passing, our happiness mortgaged to a hedonistic ideal. I think all of us were looking for a way out, an escape from the ferment. My deus ex machina came from within me, plucking me away from that existence swiftly and absolutely.

That said, I wasn't prepared for the news I got from Dr. Edward Cole when I returned to Toronto, where my family lived, for one of my sporadic visits. I had intended to stay two weeks, but never returned to Madrid to live again. Born with one damaged kidney, I had always known I needed to worry about it. But I had convinced myself, in the manner of the young, that I would make it through life with my original parts. I vividly remember, as transplantees do, the conversation that would split my life into before and after.

'We have always known your kidney might one day fail you,' began Dr. Cole, getting down to business.

We have?

'According to your blood values, it's working at 15 percent of normal. At 10 percent, we start to consider dialysis. If you don't get proper treatment and your potassium went significantly higher, you might face cardiac arrest.' He leaned back in his chair, hands clasped behind his head, with that 12-yard stare some physicians get when they gaze at a brighter landscape their patients cannot see. 'I think it's time we started thinking about a transplant for you.' 'But what about Spain?' 'If you choose to go back and ignore your medical problem - I can't stop you - you could die.'

'But my life - everything - is over there. What am I going to do with my cat?' I pleaded.

'It's your choice,' he said. Rising from his chair, he added, 'I know you've got a lot on your plate. But we have people here to help you thrash things out.'

With that, he gave me a curt pat on the shoulder and said he'd be seeing me soon. I slipped from his office to the elevator to the street. An ashen snow was falling. Spain was very far away.

Anyone who learns his kidneys are kaput - some 90,000 Americans a year - develops a special relationship to the organ. Urine becomes a magical fluid. Our brains become flypaper for urine trivia: We note that Roman emperor Vespasian had it collected from urinals to use as fertilizer, and that the Germans and the Swiss once sprinkled it on cheese for flavoring. But apart from getting hopped up about pee-pee, we also know a lot about the organs themselves. They are our silent, six-ounce chemists, cleansing the blood supply and maintaining cellular-fluid balance around the clock. From within their maroon capsules they send out hormones that regulate blood pressure, help with the production of red blood cells, and absorb calcium from the intestines.