diff --git a/src/creport.test.c b/src/creport.test.c
index 21a6c09b7..079220738 100644
--- a/src/creport.test.c
+++ b/src/creport.test.c
@@ -1,6 +1,7 @@
 #include <platform.h>
 #include "creport.h"
 #include "move.h"
+#include "spy.h"
 #include "travelthru.h"
 #include "keyword.h"
 
@@ -48,9 +49,59 @@ static void test_cr_unit(CuTest *tc) {
     test_cleanup();
 }
 
+static int cr_get_int(stream *strm, const char *match, int def)
+{
+    char line[1024];
+
+    strm->api->rewind(strm->handle);
+    while (strm->api->readln(strm->handle, line, sizeof(line))==0) {
+        if (strstr(line, match)) {
+            return atoi(line);
+        }
+    }
+    return def;
+}
+
+static void test_cr_factionstealth(CuTest *tc) {
+    stream strm;
+    faction *f1, *f2, *fr;
+    region *r;
+    unit *u;
+
+    test_setup();
+    mstream_init(&strm);
+    f1 = test_create_faction(0);
+    f2 = test_create_faction(0);
+    fr = test_create_faction(0);
+    r = test_create_region(0, 0, 0);
+    u = test_create_unit(f1, r);
+
+    cr_output_unit(&strm, u->region, f1, u, seen_unit);
+    CuAssertIntEquals(tc, f1->no, cr_get_int(&strm, ";Partei", -1));
+    CuAssertIntEquals(tc, -1, cr_get_int(&strm, ";Anderepartei", -1));
+    CuAssertIntEquals(tc, -1, cr_get_int(&strm, ";Verraeter", -1));
+
+    set_factionstealth(u, f2);
+    CuAssertPtrNotNull(tc, u->attribs);
+
+    cr_output_unit(&strm, u->region, f1, u, seen_unit);
+    CuAssertIntEquals(tc, f1->no, cr_get_int(&strm, ";Partei", -1));
+    CuAssertIntEquals(tc, f2->no, cr_get_int(&strm, ";Anderepartei", -1));
+    CuAssertIntEquals(tc, -1, cr_get_int(&strm, ";Verraeter", -1));
+
+    cr_output_unit(&strm, u->region, f2, u, seen_unit);
+    CuAssertIntEquals(tc, f1->no, cr_get_int(&strm, ";Partei", -1));
+    CuAssertIntEquals(tc, f2->no, cr_get_int(&strm, ";Anderepartei", -1));
+    CuAssertIntEquals(tc, 1, cr_get_int(&strm, ";Verraeter", -1));
+
+    mstream_done(&strm);
+    test_cleanup();
+}
+
 CuSuite *get_creport_suite(void)
 {
     CuSuite *suite = CuSuiteNew();
     SUITE_ADD_TEST(suite, test_cr_unit);
+    SUITE_ADD_TEST(suite, test_cr_factionstealth);
     return suite;
 }
diff --git a/src/spy.c b/src/spy.c
index d4082cad7..c9667f7ee 100644
--- a/src/spy.c
+++ b/src/spy.c
@@ -178,7 +178,7 @@ int spy_cmd(unit * u, struct order *ord)
     return 0;
 }
 
-void set_factionstealth(unit * u, faction * f)
+static bool can_set_factionstealth(const unit * u, const faction * f)
 {
     region *lastr = NULL;
     /* for all units mu of our faction, check all the units in the region
@@ -194,7 +194,7 @@ void set_factionstealth(unit * u, faction * f)
                     faction *fv = visible_faction(f, ru);
                     if (fv == f) {
                         if (cansee(f, lastr, ru, 0))
-                            break;
+                            return true;
                     }
                 }
                 ru = ru->next;
@@ -204,13 +204,15 @@ void set_factionstealth(unit * u, faction * f)
         }
         mu = mu->nextF;
     }
-    if (mu != NULL) {
-        attrib *a = a_find(u->attribs, &at_otherfaction);
-        if (!a)
-            a = a_add(&u->attribs, make_otherfaction(f));
-        else
-            a->data.v = f;
-    }
+    return true;
+}
+
+void set_factionstealth(unit *u, faction *f) {
+    attrib *a = a_find(u->attribs, &at_otherfaction);
+    if (!a)
+        a = a_add(&u->attribs, make_otherfaction(f));
+    else
+        a->data.v = f;
 }
 
 int setstealth_cmd(unit * u, struct order *ord)
@@ -315,7 +317,7 @@ int setstealth_cmd(unit * u, struct order *ord)
                 }
                 else {
                     struct faction *f = findfaction(nr);
-                    if (f == NULL) {
+                    if (f == NULL || !can_set_factionstealth(u, f)) {
                         cmistake(u, ord, 66, MSG_EVENT);
                         break;
                     }
diff --git a/src/spy.h b/src/spy.h
index d3ee0c728..665595ef4 100644
--- a/src/spy.h
+++ b/src/spy.h
@@ -26,12 +26,15 @@ extern "C" {
     struct region;
     struct strlist;
     struct order;
+    struct faction;
 
-    extern int setstealth_cmd(struct unit *u, struct order *ord);
-    extern int spy_cmd(struct unit *u, struct order *ord);
-    extern int sabotage_cmd(struct unit *u, struct order *ord);
-    extern void spy_message(int spy, const struct unit *u,
+    int setstealth_cmd(struct unit *u, struct order *ord);
+    int spy_cmd(struct unit *u, struct order *ord);
+    int sabotage_cmd(struct unit *u, struct order *ord);
+    void spy_message(int spy, const struct unit *u,
         const struct unit *target);
+    void set_factionstealth(struct unit * u, struct faction * f);
+    
 
 #define OCEAN_SWIMMER_CHANCE 0.1
 #define CANAL_SWIMMER_CHANCE 0.9
diff --git a/src/spy.test.c b/src/spy.test.c
index ae1550689..0dfaada7a 100644
--- a/src/spy.test.c
+++ b/src/spy.test.c
@@ -50,14 +50,6 @@ static void test_simple_spy_message(CuTest *tc) {
     test_cleanup();
 }
 
-static void set_factionstealth(unit *u, faction *f) {
-    attrib *a = a_find(u->attribs, &at_otherfaction);
-    if (!a)
-        a = a_add(&u->attribs, make_otherfaction(f));
-    else
-        a->data.v = f;
-}
-
 static void test_all_spy_message(CuTest *tc) {
     spy_fixture fix;
     item_type *itype;