For Willyto be presented at his 90th birthday celebration,

with deep respectReinhold Henneck, formerly PSI, Switzerland

Willy appeared in my life late September 1977 on the occasion of our first run at Paul-Scherrer-Institute - then still called Swiss Institute of Nuclear Physics, SIN. We went on a Saturday morning and Willy joined me in my car. I was quite nervous: the young post-doc, very late with our preparations – being helped by Prof. Häberli. What struck me already then, while chatting in the car was his casual, easy-going manner, his keen interest in other people. And when we started working he simply followed my instructions with only a raised eyebrow or an interested question here and there and it was only later that I realized that some of my preparations had been rather foolish. But he would not disturb things because he had realized that we were out of time. This was Willy right away, always unpretending, friendly, helpful and interested in people's projects and this is how he became the hero of my early physics days. That we participated both on the same experiment - the proton-proton parity violation experiment at ETH Zurich - seemed to me a rather surprising turn of events, because I had turned down Willy's offer for a post-doc position at Madison the year before. And what a difference Willy would make! There would now be weekly meetings, important decisions would be discussed within the team, reporting and archiving were standardized - in short,

the endeavor sometimes resembling a boyscout outing turned into a neatly organized and managed experiment. Looking back I still consider it a model for such a small experiment involving only a few people and essentially one institute. What impressed me most was Willy's constant drive to improve things, the systematic quest to understand the minest detail, to hunt for systematic effects and to prepare for all kinds of unexpected surprises. And his dedication! I remember one Saturday afternoon when I ran into Willy who helped Sam Jaccard - the SIN responsable for the polarized ion source - with a dedicated performance test of the old source ionizer. The result was that we decided to buy a new ionizer which allowed us to run at world-record polarized proton currents - one of the keys to the experiment.Of course, since he usually spent several weeks at a time in Zurich, we also shared quite a bit of our free time together, went hiking or skiing. This was always good fun and I could even here learn from Willy's openminded, easygoing attitude in meeting people, his humour and his curiosity in all aspects of life. To which people responded gladly. He seemed to be everbody's darling and nearly always was the center of attention.

1985, at the Osaka Polarization conference, with my later wife.

I remember one night in 1980 when he arrived late at our weekly get-together with my friends at the 'bodega', in the company of a very shy, very young, lovely lady. They seemed to have met at some kind of evening lecture, but it never became clear who picked up whom. She was Gabi, his later wife. Here is the two of them, in 1989, at lake Madison.

Willy's wit and humour were legendary - and still are as quick as ever – see here his reply to my menu suggestion from Vietnam 2014 :

Stir fried better than stewed!!!!Willy