diff --git a/src/ISO8601.cpp b/src/ISO8601.cpp
index d9ef406f3..3985b34a7 100644
--- a/src/ISO8601.cpp
+++ b/src/ISO8601.cpp
@@ -954,6 +954,13 @@ int ISO8601d::weekOfYear (int weekStart) const
   return weekNumber;
 }
 
+////////////////////////////////////////////////////////////////////////////////
+int ISO8601d::dayOfWeek () const
+{
+  struct tm* t = localtime (&_date);
+  return t->tm_wday;
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 void ISO8601p::clear ()
 {
diff --git a/src/ISO8601.h b/src/ISO8601.h
index db35dff1d..9830c7177 100644
--- a/src/ISO8601.h
+++ b/src/ISO8601.h
@@ -58,6 +58,7 @@ public:
   int day () const;
   int year () const;
   int weekOfYear (int) const;
+  int dayOfWeek () const;
 
 private:
   void clear ();