Thank you Patricia - - I knew you could be counted on to find the word which was stubbornly eluding me! But seriously -- great software evolves. It has never been known not to. One of the reasons Xy/NB is effectively dead is that it is not evolving to meet the needs of new customers. I must say I am grateful we have it as a DOS program. That more or less ensures perpetual usability. There are plenty of early Windows programs of great utility that don't work today. Re open-source - - when is the last time anyone talked to Ken Frank? Where is he? What's he doing? How do we know he wouldn't be delighted to open-source the code and rights? Has anyone been in touch with the divine Dave Ericsson lately ? What can we do to evangelize XyWrite today?I really don't think you meant "polarity"; parity, maybe?