Example

This EXEC called from the ISPF Primary Option panel:

/*  REXX  */
ADDRESS  ISPEXEC
"ADDPOP"
"DISPLAY PANEL(PANELA)"
"ADDPOP POPLOC(FIELD2)"
ZWINTTL = "POPUP WINDOW TITLE"
"DISPLAY PANEL(PANELB)"
"ADDPOP COLUMN(5) ROW(3)"
ZWINTTL = ""
"DISPLAY PANEL(PANELC)"
EXIT

results in this panel:

Figure 1. Multiple Pop-up Windows