diff --git a/src/Type.cc b/src/Type.cc
index e9b0949d13..34ad207842 100644
--- a/src/Type.cc
+++ b/src/Type.cc
@@ -96,6 +96,7 @@ BroType::BroType(TypeTag t, bool arg_base_type)
 	case TYPE_LIST:
 	case TYPE_FUNC:
 	case TYPE_FILE:
+	case TYPE_OPAQUE:
 	case TYPE_VECTOR:
 	case TYPE_TYPE:
 		internal_tag = TYPE_INTERNAL_OTHER;
@@ -1262,6 +1263,42 @@ bool FileType::DoUnserialize(UnserialInfo* info)
 	return yield != 0;
 	}
 
+OpaqueType::OpaqueType(const string& name)
+: BroType(TYPE_OPAQUE), name(name)
+	{
+	}
+
+void OpaqueType::Describe(ODesc* d) const
+	{
+	if ( d->IsReadable() )
+		d->AddSP("opaque of");
+	else
+		d->Add(int(Tag()));
+
+	d->Add(name.c_str());
+	}
+
+// TODO: Serialization semantics not yet defined.
+//
+// IMPLEMENT_SERIAL(OpaqueType, SER_OPAQUE_TYPE);
+// 
+// bool OpaqueType::DoSerialize(SerialInfo* info) const
+// 	{
+// 	DO_SERIALIZE(SER_OPAQUE_TYPE, BroType);
+// 	return SERIALIZE(name);
+// 	}
+// 
+// bool OpaqueType::DoUnserialize(UnserialInfo* info)
+// 	{
+// 	DO_UNSERIALIZE(BroType);
+// 
+// 	char const* n;
+// 	if ( ! UNSERIALIZE_STR(&n, 0) );
+// 	  return false;
+// 	name = n;
+// 	return true;
+// 	}
+
 EnumType::EnumType(const string& arg_name)
 : BroType(TYPE_ENUM)
 	{
@@ -1716,6 +1753,10 @@ int same_type(const BroType* t1, const BroType* t2, int is_init)
 	case TYPE_FILE:
 		return same_type(t1->YieldType(), t2->YieldType(), is_init);
 
+  case TYPE_OPAQUE:
+    // FIXME: Should we downcast here and compare the opaque type names?
+    return 1;
+
 	case TYPE_TYPE:
 		return same_type(t1, t2, is_init);
 
@@ -1805,6 +1846,7 @@ int is_assignable(BroType* t)
 
 	case TYPE_VECTOR:
 	case TYPE_FILE:
+	case TYPE_OPAQUE:
 	case TYPE_TABLE:
 	case TYPE_TYPE:
 		return 1;
diff --git a/src/Type.h b/src/Type.h
index 8e2bb099d8..21b4bc2023 100644
--- a/src/Type.h
+++ b/src/Type.h
@@ -29,6 +29,7 @@ typedef enum {
 	TYPE_LIST,
 	TYPE_FUNC,
 	TYPE_FILE,
+	TYPE_OPAQUE,
 	TYPE_VECTOR,
 	TYPE_TYPE,
 	TYPE_ERROR
@@ -499,6 +500,24 @@ protected:
 	BroType* yield;
 };
 
+class OpaqueType : public BroType {
+public:
+	OpaqueType(const string& name);
+	virtual ~OpaqueType() { };
+
+	const string& Name()	{ return name; }
+
+	void Describe(ODesc* d) const;
+
+protected:
+	OpaqueType() { }
+
+  // TODO: Serialization semantics not yet defined.
+	//DECLARE_SERIAL(OpaqueType)
+
+	const string name;
+};
+
 class EnumType : public BroType {
 public:
 	EnumType(const string& arg_name);
diff --git a/src/parse.y b/src/parse.y
index b4eee1a56c..c442ffbd72 100644
--- a/src/parse.y
+++ b/src/parse.y
@@ -11,7 +11,7 @@
 %token TOK_DOUBLE TOK_ELSE TOK_ENUM TOK_EVENT TOK_EXPORT TOK_FILE TOK_FOR
 %token TOK_FUNCTION TOK_GLOBAL TOK_HOOK TOK_ID TOK_IF TOK_INT
 %token TOK_INTERVAL TOK_LIST TOK_LOCAL TOK_MODULE
-%token TOK_NEXT TOK_OF TOK_PATTERN TOK_PATTERN_TEXT
+%token TOK_NEXT TOK_OF TOK_OPAQUE TOK_PATTERN TOK_PATTERN_TEXT
 %token TOK_PORT TOK_PRINT TOK_RECORD TOK_REDEF
 %token TOK_REMOVE_FROM TOK_RETURN TOK_SCHEDULE TOK_SET
 %token TOK_STRING TOK_SUBNET TOK_SWITCH TOK_TABLE
@@ -890,6 +890,12 @@ type:
 				$$ = new FileType(base_type(TYPE_STRING));
 				}
 
+	|	TOK_OPAQUE TOK_OF TOK_ID
+				{
+				set_location(@1, @3);
+				$$ = new OpaqueType($3);
+				}
+
 	|	resolve_id
 			{
 			if ( ! $1 || ! ($$ = $1->AsType()) )
diff --git a/src/scan.l b/src/scan.l
index 4e1a66144e..b231e11d74 100644
--- a/src/scan.l
+++ b/src/scan.l
@@ -298,6 +298,7 @@ local	return TOK_LOCAL;
 module	return TOK_MODULE;
 next	return TOK_NEXT;
 of	return TOK_OF;
+opaque	return TOK_OPAQUE;
 pattern	return TOK_PATTERN;
 port	return TOK_PORT;
 print	return TOK_PRINT;