diff --git a/tren.py b/tren.py
index f085e38..d949f55 100755
--- a/tren.py
+++ b/tren.py
@@ -8,7 +8,7 @@
 PROGNAME = "tren.py"
 BASENAME = PROGNAME.split(".py")[0]
 PROGENV  = BASENAME.upper()
-RCSID = "$Id: tren.py,v 1.165 2010/03/05 19:05:23 tundra Exp $"
+RCSID = "$Id: tren.py,v 1.166 2010/03/05 21:54:36 tundra Exp $"
 VERSION = RCSID.split()[2]
 
 # Copyright Information
@@ -98,7 +98,15 @@
 OPTINTRO     =  "-"           # Option introducer
 RANGESEP     =  ":"           # Separator for instance ranges
 SINGLEINST   =  "SINGLEINST"  # Indicates a single, not range, replacement instance
-TOKENDELIM   =  "/"""         # Symbol used to delimit renaming tokens
+
+
+#####
+# Replacement Token Literals
+#####
+
+TOKENDELIM   =  "/"           # Symbol used to delimit renaming tokens
+TOKENENV     =  "$"           # Environment variable token
+
 
 # Internal program state literals
 
@@ -682,7 +690,7 @@
                 
         # There must be an even number of token delimiters
         # or the renaming token is malformed
-
+        
         if rentokens and  len(rentokens[-1]) != 2:
             ErrorMsg(eBADRENAMETOK % renstring)
 
@@ -695,6 +703,22 @@
             rentokens[i].append(renstring[rentokens[i][0]+1 : rentokens[i][1]])
             i += 1
 
+        # Process each token.  Work left to right so as not to mess up
+        # the previously stored indexes.
+
+        rentokens.reverse()
+
+        for r in rentokens:
+
+            # Environment variable replacement token
+            
+            if r[2].startswith(TOKENENV):
+                r[2] = os.getenv(r[2][1:])
+            
+            # Do the actual replacement
+
+            renstring = renstring[:r[0]] + r[2] + renstring[r[1]+1:]
+            
         return renstring
 
     # End of '__ResolveRenameTokens()'