diff --git a/ibitset.h b/ibitset.h
index 18975dc2..23ca4bc9 100644
--- a/ibitset.h
+++ b/ibitset.h
@@ -53,6 +53,11 @@ namespace etl
     {
     }
 
+    //*************************************************************************
+    /// The size of the bitset.
+    //*************************************************************************
+    virtual size_t size() const = 0;
+
     //*************************************************************************
     /// Check the bit at the position.
     //*************************************************************************
@@ -68,6 +73,11 @@ namespace etl
     //*************************************************************************
     virtual ibitset& reset(size_t position) = 0;
 
+    //*************************************************************************
+    /// Reset all the bits.
+    //*************************************************************************
+    virtual ibitset& reset() = 0;
+
     //*************************************************************************
     /// Finds the first bit in the specified state.
     ///\param state The state to search for.