diff --git a/src/attackminimize.c b/src/attackminimize.c
index 13ef899..79cbb1e 100644
--- a/src/attackminimize.c
+++ b/src/attackminimize.c
@@ -1,6 +1,6 @@
 #include <stdio.h>
 #include <stdlib.h>
-#include "runs.h"
+#include "system.h"
 #include "tracebuf.h"
 
 //! Help counter for the number of unknowns.
diff --git a/src/claims.c b/src/claims.c
index 986e37e..e8ada33 100644
--- a/src/claims.c
+++ b/src/claims.c
@@ -1,6 +1,6 @@
 #include <stdlib.h>
 #include "termmaps.h"
-#include "runs.h"
+#include "system.h"
 #include "error.h"
 
 #define MATCH_NONE 0
diff --git a/src/compiler.c b/src/compiler.c
index 95ebee0..a2e7912 100644
--- a/src/compiler.c
+++ b/src/compiler.c
@@ -4,7 +4,7 @@
 #include "terms.h"
 #include "termlists.h"
 #include "memory.h"
-#include "runs.h"
+#include "system.h"
 #include "knowledge.h"
 #include "symbols.h"
 #include "substitutions.h"
@@ -40,7 +40,7 @@ Termlist tacTermlist (Tac tc);
 
 /* externally used:
  * TERM_Function in termlists.c for inversekeys
- * TERM_Type in runs.c for type determination.
+ * TERM_Type in system.c for type determination.
  */
 
 Term TERM_Agent;
diff --git a/src/constraints.c b/src/constraints.c
index 8066345..8400053 100644
--- a/src/constraints.c
+++ b/src/constraints.c
@@ -2,7 +2,7 @@
 #include "memory.h"
 #include "constraints.h"
 #include "debug.h"
-#include "runs.h"
+#include "system.h"
 
 
 
diff --git a/src/debug.c b/src/debug.c
index dd4d8bf..094b5fa 100644
--- a/src/debug.c
+++ b/src/debug.c
@@ -7,7 +7,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include "debug.h"
-#include "runs.h"
+#include "system.h"
 
 static int debuglevel;
 
diff --git a/src/knowledge.c b/src/knowledge.c
index 12fd051..700511f 100644
--- a/src/knowledge.c
+++ b/src/knowledge.c
@@ -9,7 +9,7 @@
 #include "termlists.h"
 #include "knowledge.h"
 #include "memory.h"
-#include "runs.h"
+#include "system.h"
 #include "debug.h"
 
 /*
diff --git a/src/latex.c b/src/latex.c
index 9e46dcc..f83f58c 100644
--- a/src/latex.c
+++ b/src/latex.c
@@ -6,7 +6,7 @@
 #include <stdlib.h>
 #include <time.h>
 #include <limits.h>
-#include "runs.h"
+#include "system.h"
 #include "memory.h"
 #include "modelchecker.h"
 #include "tracebuf.h"
diff --git a/src/latex.h b/src/latex.h
index f9730f0..7dab51e 100644
--- a/src/latex.h
+++ b/src/latex.h
@@ -5,7 +5,7 @@
 #ifndef LATEX
 #define LATEX
 
-#include "runs.h"
+#include "system.h"
 
 void latexInit(const System sys, int argc, char **argv);
 void latexDone(const System sys);
diff --git a/src/main.c b/src/main.c
index 727984d..7b1cbdf 100644
--- a/src/main.c
+++ b/src/main.c
@@ -36,7 +36,7 @@
 #include <stdio.h>
 #include <time.h>
 #include <limits.h>
-#include "runs.h"
+#include "system.h"
 #include "debug.h"
 #include "modelchecker.h"
 #include "memory.h"
diff --git a/src/match_basic.c b/src/match_basic.c
index 1085525..b56ec19 100644
--- a/src/match_basic.c
+++ b/src/match_basic.c
@@ -9,7 +9,7 @@
 #include <stdio.h>
 #include "memory.h"
 #include "substitutions.h"
-#include "runs.h"
+#include "system.h"
 #include "modelchecker.h"
 #include "match_basic.h"
 
diff --git a/src/match_clp.c b/src/match_clp.c
index 97d1c37..1ac406c 100644
--- a/src/match_clp.c
+++ b/src/match_clp.c
@@ -10,7 +10,7 @@
 #include <stdlib.h>
 #include <stdio.h>
 #include "match_clp.h"
-#include "runs.h"
+#include "system.h"
 #include "memory.h"
 #include "constraints.h"
 #include "mgu.h"
diff --git a/src/match_clp.h b/src/match_clp.h
index dae1660..c50b93d 100644
--- a/src/match_clp.h
+++ b/src/match_clp.h
@@ -1,7 +1,7 @@
 #ifndef MATCHCLP
 #define MATCHCLP
 
-#include "runs.h"
+#include "system.h"
 
 int matchRead_clp (const System sys, const int run,
 		   int (*proceed) (System, int));
diff --git a/src/memory.c b/src/memory.c
index cf863a8..44be6ed 100644
--- a/src/memory.c
+++ b/src/memory.c
@@ -26,7 +26,7 @@
 #include "termlists.h"
 #include "knowledge.h"
 #include "substitutions.h"
-#include "runs.h"
+#include "system.h"
 
 //! Open memory code.
 void
diff --git a/src/modelchecker.c b/src/modelchecker.c
index ccf6da4..5354ee7 100644
--- a/src/modelchecker.c
+++ b/src/modelchecker.c
@@ -9,7 +9,7 @@
 #include <limits.h>
 #include "substitutions.h"
 #include "knowledge.h"
-#include "runs.h"
+#include "system.h"
 #include "debug.h"
 #include "modelchecker.h"
 #include "report.h"
diff --git a/src/output.c b/src/output.c
index d7c2175..324d263 100644
--- a/src/output.c
+++ b/src/output.c
@@ -8,7 +8,7 @@
 
 #include <stdlib.h>
 #include <stdio.h>
-#include "runs.h"
+#include "system.h"
 #include "latex.h"
 
 
diff --git a/src/output.h b/src/output.h
index 5c9b8a4..3a3f9fb 100644
--- a/src/output.h
+++ b/src/output.h
@@ -1,7 +1,7 @@
 #ifndef OUTPUT
 #define OUTPUT
 
-#include "runs.h"
+#include "system.h"
 
 void tracePrint(const System sys);
 void attackDisplay(const System sys);
diff --git a/src/pheading.h b/src/pheading.h
index 61a084a..a69c035 100644
--- a/src/pheading.h
+++ b/src/pheading.h
@@ -8,6 +8,6 @@
 #include "terms.h"
 #include "termlists.h"
 #include "symbols.h"
-#include "runs.h"
+#include "system.h"
 #include "tac.h"
 #endif
diff --git a/src/report.c b/src/report.c
index c169736..20d1b53 100644
--- a/src/report.c
+++ b/src/report.c
@@ -1,7 +1,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include "terms.h"
-#include "runs.h"
+#include "system.h"
 #include "debug.h"
 #include "output.h"
 
diff --git a/src/roles.c b/src/roles.c
index b2a9ea4..6bdbcca 100644
--- a/src/roles.c
+++ b/src/roles.c
@@ -8,7 +8,7 @@
 #include "terms.h"
 #include "termlists.h"
 #include "knowledge.h"
-#include "runs.h"
+#include "system.h"
 #include "memory.h"
 #include "constraints.h"
 #include "debug.h"
@@ -16,7 +16,7 @@
 #include "tracebuf.h"
 #include "roles.h"
 
-extern int globalLatex;		// from runs.c
+extern int globalLatex;		// from system.c
 
 //! Allocate memory the size of a roledef struct.
 Roledef
diff --git a/src/substitutions.h b/src/substitutions.h
index 0997859..9fbb58b 100644
--- a/src/substitutions.h
+++ b/src/substitutions.h
@@ -3,7 +3,7 @@
 
 #include "termlists.h"
 #include "knowledge.h"
-#include "runs.h"
+#include "system.h"
 
 struct substitution
 {
diff --git a/src/runs.c b/src/system.c
similarity index 99%
rename from src/runs.c
rename to src/system.c
index 2029e02..3b5bcec 100644
--- a/src/runs.c
+++ b/src/system.c
@@ -8,7 +8,7 @@
 #include "terms.h"
 #include "termlists.h"
 #include "knowledge.h"
-#include "runs.h"
+#include "system.h"
 #include "memory.h"
 #include "constraints.h"
 #include "debug.h"
diff --git a/src/runs.h b/src/system.h
similarity index 100%
rename from src/runs.h
rename to src/system.h
diff --git a/src/tracebuf.c b/src/tracebuf.c
index 9419753..eb4b217 100644
--- a/src/tracebuf.c
+++ b/src/tracebuf.c
@@ -6,7 +6,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
-#include "runs.h"
+#include "system.h"
 #include "memory.h"
 #include "tracebuf.h"
 #include "varbuf.h"
diff --git a/src/tracebuf.h b/src/tracebuf.h
index 1b95482..79a42fe 100644
--- a/src/tracebuf.h
+++ b/src/tracebuf.h
@@ -4,7 +4,7 @@
 #include "terms.h"
 #include "termlists.h"
 #include "knowledge.h"
-#include "runs.h"
+#include "system.h"
 
 /* STATUS symbols */
 #define S_UNK 0 // UNKnown   : unprocessed.
@@ -15,7 +15,7 @@
 
 
 /*
- * tracebuf struct is defined in runs.h to avoid loops.
+ * tracebuf struct is defined in system.h to avoid loops.
  */
 
 int tracebufRebuildKnow(struct tracebuf *tb);
diff --git a/src/varbuf.c b/src/varbuf.c
index 7e064a7..c6f5f20 100644
--- a/src/varbuf.c
+++ b/src/varbuf.c
@@ -2,11 +2,11 @@
  * varbuf.c
  *
  * Operations on a variable substitutions buffer.
- * The type is actually defined in runs.h
+ * The type is actually defined in system.h
  */
 
 #include "memory.h"
-#include "runs.h"
+#include "system.h"
 
 /*
  * create a new varbuffer from the current state of the system
diff --git a/src/varbuf.h b/src/varbuf.h
index 6bc454d..9467e82 100644
--- a/src/varbuf.h
+++ b/src/varbuf.h
@@ -1,7 +1,7 @@
 #ifndef VARBUF
 #define VARBUF
 
-#include "runs.h"
+#include "system.h"
 
 Varbuf varbufInit (const System sys);
 void varbufSet (const System sys, Varbuf vb);