diff --git a/Log.cc b/Log.cc
index ff33d934001b18ca6724f3aba3b2ca07baf2af81..679b4552f1877b8b16935a52cfeed6cc1a4f9e6b 100644
--- a/Log.cc
+++ b/Log.cc
@@ -7,6 +7,10 @@
 /*  CCOPYRIGHT  */
 
 #include "Log.h"
+#include <iostream>
+#include <fstream>
+#include <strstream>
+#include <string>
 
 namespace Utilities {
 
diff --git a/log.h b/log.h
index 92f06593a308ac2367425cd2ccbdfe0540618853..25014a4cec370d7b4653fcacd6af8518a8660aa9 100644
--- a/log.h
+++ b/log.h
@@ -17,6 +17,11 @@ determining streaming to the Logfile and/or cout. */
 #if !defined(log_h)
 #define log_h
 
+#include <iostream>
+#include <fstream>
+#include <string>
+#include <iomanip>
+#include <strstream>
 #include "newmat/newmatap.h"
 #include "newmat/newmatio.h"
 
diff --git a/options.h b/options.h
index 2d3fa5a9ff5fa5968c52b1c4659bcca87ea53ff8..a8c0c12a8138232c6d87c1a61cda92a5509a6fe4 100644
--- a/options.h
+++ b/options.h
@@ -2,6 +2,10 @@
 #if !defined(OPTIONS_H)
 #define OPTIONS_H
 
+#include <stdexcept>
+#include <string>
+#include <vector>
+#include <iostream>
 
 #define POSIX_SOURCE 1
 
diff --git a/time_tracer.cc b/time_tracer.cc
index e66d405d192b52c0a292485c0c675b55def4be93..31d3e4fe16c41f0bd6c0f54791265d99dd6701d6 100644
--- a/time_tracer.cc
+++ b/time_tracer.cc
@@ -7,6 +7,11 @@
 /*  CCOPYRIGHT  */
 
 #include "time_tracer.h"
+#include <iostream>
+#include <fstream>
+#include <strstream>
+#include <string>
+#include <set>
 
 namespace Utilities {
 
diff --git a/time_tracer.h b/time_tracer.h
index a4d83f2c56021763181e3657974dbeab06110e61..171453bb7c0e10a09d3dcf52f51929026c182400 100644
--- a/time_tracer.h
+++ b/time_tracer.h
@@ -9,6 +9,13 @@
 #if !defined(Time_Tracer_h)
 #define Time_Tracer_h
 
+#include <iostream>
+#include <fstream>
+#include <string>
+#include <time.h>
+#include <set>
+#include <stack>
+#include <iterator>
 
 using namespace std;
 
diff --git a/tracer_plus.h b/tracer_plus.h
index 44dc321a27b759553427f50e8f475a3983eb5580..1efe1ae5add5631daede141710672a5685f65a98 100644
--- a/tracer_plus.h
+++ b/tracer_plus.h
@@ -9,6 +9,11 @@
 #if !defined(Tracer_Plus_h)
 #define Tracer_Plus_h
 
+#include <iostream>
+#include <fstream>
+#include <string>
+#include <time.h>
+#include <set>
 #include "newmat/newmatap.h"
 #include "newmat/newmatio.h"
 #include "time_tracer.h"