diff --git a/lib/parse_mac.cc b/lib/parse_mac.cc
index 0d84250..4007a1d 100644
--- a/lib/parse_mac.cc
+++ b/lib/parse_mac.cc
@@ -20,6 +20,7 @@
 #include <gnuradio/block_detail.h>
 #include <gnuradio/io_signature.h>
 #include <string>
+#include <iomanip>
 #include <boost/format.hpp> 
 
 using namespace gr::ieee802_11;