diff --git a/src/faction.c b/src/faction.c
index 2677f93..cb8fa83 100644
--- a/src/faction.c
+++ b/src/faction.c
@@ -70,6 +70,12 @@ char* faction_longname(int f) {
 void faction_modPlayer(int f, int mod) {
   if(faction_isFaction(f)) {
     faction_stack[f].player += mod;
+
+    /* Sanitize. */
+    if(faction_stack[f].player > 100)
+      faction_stack[f].player = 100;
+    else if(faction_stack[f].player < -100)
+      faction_stack[f].player = -100;
   } else {
     DEBUG("%d is an invalid faction/alliance", f);
     return;