Early investigation of virtual machine subsystem flexibility centered on telecommunications support and intercomputer networking and proceeded in two phases. The first phase focused on an experimental program for the virtual machine control program CP-67 that supported remote work stations and pioneered intercomputer spool communications. The results of that effort inspired a second effort in the same area with some significant redirection. This second phase ultimately led to the remote spooling communications subsystem component of VM/370, the VM/370 networking package (VNET), and a large network of interactive computer systems within IBM. These phases are discussed along with suggestions for sev-eral continuing lines of work based on current results.