diff --git a/Operand.cpp b/Operand.cpp
index d2bd0b5..9b5c850 100644
--- a/Operand.cpp
+++ b/Operand.cpp
@@ -86,10 +86,21 @@ namespace jet {
 	 } else
 	   throw coreutils::Exception("Expecting ) at end of TRIM expression.");	 	 	 
       } else if(in.ifNextIgnoreCase("TOUPPER")) {
-	 
-
+	 if(!in.ifNext("("))
+	   throw coreutils::Exception("Expecting ( for TOUPPER parameters.");
+	 Operand parm1(in, tag);
+	 if(in.ifNext(")")) {
+	    string = parm1.string.toUpper();
+	 } else
+	   throw coreutils::Exception("Expecting ) at end of TOUPPER expression.");	 	 	 	 
       } else if(in.ifNextIgnoreCase("TOLOWER")) {
-	 
+	 if(!in.ifNext("("))
+	   throw coreutils::Exception("Expecting ( for TOLOWER parameters.");
+	 Operand parm1(in, tag);
+	 if(in.ifNext(")")) {
+	    string = parm1.string.toLower();
+	 } else
+	   throw coreutils::Exception("Expecting ) at end of TOLOWER expression.");	 	 	 	 	 
       } else if(in.ifNextIgnoreCase("REVERSE")) {
 	 
       } else if(in.ifNextIgnoreCase("CONCAT")) {
diff --git a/tests/testvar.jet b/tests/testvar.jet
index 89c02b4..b10195f 100755
--- a/tests/testvar.jet
+++ b/tests/testvar.jet
@@ -21,4 +21,7 @@ $[ix]
 $[ix]
 <set name="test64" value="this is a test" />
 $[test64;tobase64]
+$[test64;toupper]
+<set name="testupperexpr" expr="toupper($[test64])" />
+$[testupperexpr]
 </jet>