All, Thanks for your responses. As always I have more information than I can easily digest. It looks like I have some reading to do.
Mark suggested that I look into Mirth, and I definitely have an eye towards integration with that project. However, I am very concerned with human side interfaces, which I do not think Mirth does yet. (I understand that might be changing!!) The other is the "email analogy". I do want people to think of email with my system, because that is relatively easy to understand. Heck, e-mail itself is a technology that references the prior model (snail mail). So I am going with the KISS principle for now. Does anyone know what kind of messaging is available in VistA? -FT -- Fred Trotter http://www.fredtrotter.com