PB-PK Summary

 Thanks to all who replied!
 In short, there are quite a few packages in use.
 ACSL and SimuSolv which I mentioned in the original posting and...
 MATLAB with the Simulink Module (contact henk (- at -) qsar.ritox.dgk.ruu.nl)
 Scientist (from ACS software)
 Stella (from High Performance Systems)
 and of course, RS/1, SAS, Autoan/Nonlin.
 I have decided to test Stella. This package apparently runs on PCs
 and Macs, has a very flexible and intuitive graphical interface,
 and is relatively inexpensive (a rare commodity these days).
 I will be willing to share my experiences with all interested parties.
 *Chris L. Waller, Ph.D.                          PHONE 919-541-7976*
 *Research Chemist                                FAX   919-541-5394*
 *waller (- at -) thor.herl.epa.gov                                          *
 *Pharmacokinetics Branch (MD-74)                                   *
 *ETD/HERL/USEPA                                                    *
 *Research Triangle Park, NC 27711                                  *
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