The British APL Association is saddened to hear of the passing of Ian Sharp, one of the founding members of IPSA. A number of those involved in the BAA including myself worked for IPSA, and I would say it was the best work environment I have ever worked in.
IPSA knew that by trusting and respecting employees you create something special and, when you need them most, staff will come through and push hard to get the job done. This approach was driven by Ian and it is notable how all those who worked for IPSA still hold those days in high regard.
I cannot hope to write anything better than the obituary on the Dyalog Website so I will just add a link to the relevant page: