diff --git a/ast_types.py b/ast_types.py
index 1f07370..c7c31b3 100644
--- a/ast_types.py
+++ b/ast_types.py
@@ -8,6 +8,13 @@
     def __repr__(self):
         return "Reference('%s')" % (self.value)
 
+class Bool:
+    def __init__(self, value):
+        self.value = value
+
+    def __repr__(self):
+        return "Bool(%s)" % (self.value)
+
 class Text:
     def __init__(self, value):
         self.value = value
diff --git a/interp.py b/interp.py
index b1571e1..9d0500e 100644
--- a/interp.py
+++ b/interp.py
@@ -4,6 +4,19 @@
 import ast_types
 import sys
 
+class Bool:
+    def __init__(self, value):
+        self._value = value
+
+    def __repr__(self):
+        return "Bool(%s)" % (self._value)
+
+    def value(self):
+        return self._value
+
+    def verb_ToText(self, args):
+        return Text(self._value)
+
 class Text:
     def __init__(self, value):
         self._value = value
@@ -58,6 +71,8 @@
                 raise InterpreterError("Unknown environment value %s" % (value.value))
         elif value.__class__ == ast_types.Text:
             return Text(value.value)
+        elif value.__class__ == ast_types.Bool:
+            return Bool(value.value)
         else:
             raise InterpreterError("Unknown value type %s" % (value.__class__.__name__))
 
diff --git a/parse.py b/parse.py
index 96ef191..8eba8e1 100644
--- a/parse.py
+++ b/parse.py
@@ -126,6 +126,9 @@
             elif token == "BeginText":
                 type = "text"
                 value = self.read_text(line, column)
+            elif token in ["True", "False"]:
+                type = "bool"
+                value = (token == "True")
             elif token in keywords:
                 type = "keyword"
                 value = token
@@ -184,6 +187,8 @@
             ret = ast_types.Reference(value)
         elif type == "text":
             ret = ast_types.Text(value)
+        elif type == "bool":
+            ret = ast_types.Bool(value)
         else:
             raise ParseError(context, "Unexpected value type %s" % (type))
         log.log(log.PARSER, log.TRACE, "Parsed value, AST is %s" % (ret))
@@ -279,8 +284,8 @@
 
     def parse_directive(self, context):
         token = self.peek()
-        if token.type != "keyword" and token.type != "symbol":
-            raise ParseError(context, "Expected keyword or symbol, got %s" % (token.type))
+        if token.type != "keyword" and token.type != "symbol" and token.type != "bool":
+            raise ParseError(context, "Expected keyword, symbol or bool, got %s" % (token.type))
         if token.type == "keyword":
             if token.value == "Set":
                 return self.parse_set(context)