diff --git a/DDG4/lcio/Geant4Output2LCIO.cpp b/DDG4/lcio/Geant4Output2LCIO.cpp
index f8a20ef0c27b767a1fa16409abfc06a363494204..d8bc746872bf5ebfd95a9c221b756426a1264e7c 100644
--- a/DDG4/lcio/Geant4Output2LCIO.cpp
+++ b/DDG4/lcio/Geant4Output2LCIO.cpp
@@ -25,6 +25,8 @@
 #include "IMPL/LCEventImpl.h"
 #include "IMPL/LCCollectionVec.h"
 
+using namespace lcio ;
+
 /// Namespace for the AIDA detector description toolkit
 namespace DD4hep {
 
diff --git a/DDG4/lcio/LCIOConversions.cpp b/DDG4/lcio/LCIOConversions.cpp
index 8e1772b78770f6aa2ea076c9982e7663659512d8..7ce88363b1d1f2900cd5da0c827e72ba52c12f19 100644
--- a/DDG4/lcio/LCIOConversions.cpp
+++ b/DDG4/lcio/LCIOConversions.cpp
@@ -24,6 +24,7 @@
 #include "DDG4/Geant4Data.h"
 
 // LCIO includes
+#include "lcio.h"
 #include "IMPL/LCCollectionVec.h"
 //
 #include "IMPL/LCEventImpl.h"
@@ -38,7 +39,7 @@
 #include <G4SystemOfUnits.hh>
 
 using namespace std;
-
+using namespace lcio ;
 //==================================================================================
 //
 // SimCalorimeterHit:
diff --git a/DDG4/lcio/LCIOFileReader.cpp b/DDG4/lcio/LCIOFileReader.cpp
index 0a8cf0eda534bf85a094b43c439958707753f800..b98153608e98555923f41813735fa53173d2e9ea 100644
--- a/DDG4/lcio/LCIOFileReader.cpp
+++ b/DDG4/lcio/LCIOFileReader.cpp
@@ -16,6 +16,9 @@
 
 // Framework include files
 #include "LCIOEventReader.h"
+#include "lcio.h"
+
+using namespace lcio ;
 
 // Forward declarations
 namespace IO { class LCReader; }