diff -Nur -Xp1/diff_ignore orig/common/city.c p1/common/city.c
--- orig/common/city.c	Thu Oct  4 22:34:39 2001
+++ p1/common/city.c	Wed Oct 10 18:44:15 2001
@@ -1965,6 +1965,9 @@
       city_got_building(pcity, B_PALACE)) val /= 2;
   val *= g->corruption_level;
   val /= 100;
+
+  /* trade penalty if city is smaller than fulltradesize */
+  val = MAX(val, trade * (game.fulltradesize - pcity->size) * 3 / 2 / game.fulltradesize);
   if (val > trade)
     val = trade;
   return (val);			/* how did y'all let me forget this one? -- Syela */
diff -Nur -Xp1/diff_ignore orig/common/game.c p1/common/game.c
--- orig/common/game.c	Sat Oct  6 15:44:49 2001
+++ p1/common/game.c	Wed Oct 10 18:44:15 2001
@@ -715,6 +715,7 @@
   game.fogofwar    = GAME_DEFAULT_FOGOFWAR;
   game.fogofwar_old= game.fogofwar;
   game.auto_ai_toggle = GAME_DEFAULT_AUTO_AI_TOGGLE;
+  game.fulltradesize  = GAME_DEFAULT_FULLTRADESIZE;
   game.barbarianrate  = GAME_DEFAULT_BARBARIANRATE;
   game.onsetbarbarian = GAME_DEFAULT_ONSETBARBARIAN;
   game.nbarbarians = 0;
diff -Nur -Xp1/diff_ignore orig/common/game.h p1/common/game.h
--- orig/common/game.h	Sun Sep 16 22:27:13 2001
+++ p1/common/game.h	Wed Oct 10 18:44:15 2001
@@ -73,6 +73,7 @@
   int diplchance;
   int cityfactor;
   int civilwarsize;
+  int fulltradesize;
   int min_players, max_players, nplayers;
   int aifill;
   int barbarianrate;
@@ -377,6 +378,10 @@
 #define GAME_DEFAULT_PINGTIMEOUT     60
 #define GAME_MIN_PINGTIMEOUT         60
 #define GAME_MAX_PINGTIMEOUT         1800
+
+#define GAME_DEFAULT_FULLTRADESIZE   1
+#define GAME_MIN_FULLTRADESIZE       1
+#define GAME_MAX_FULLTRADESIZE       150
 
 #define GAME_DEFAULT_BARBARIANRATE   2
 #define GAME_MIN_BARBARIANRATE       0
diff -Nur -Xp1/diff_ignore orig/server/savegame.c p1/server/savegame.c
--- orig/server/savegame.c	Wed Oct  3 11:31:06 2001
+++ p1/server/savegame.c	Wed Oct 10 18:44:15 2001
@@ -2004,6 +2004,7 @@
     game.warminglevel  = secfile_lookup_int(file, "game.warminglevel");
     game.nuclearwinter = secfile_lookup_int_default(file, 0, "game.nuclearwinter");
     game.coolinglevel  = secfile_lookup_int_default(file, 8, "game.coolinglevel");
+    game.fulltradesize = secfile_lookup_int_default(file, 1, "game.fulltradesize");
     game.unhappysize   = secfile_lookup_int(file, "game.unhappysize");
     game.angrycitizen  = secfile_lookup_int_default(file, 0, "game.angrycitizen");
 
@@ -2366,6 +2367,7 @@
   secfile_insert_int(file, game.warminglevel, "game.warminglevel");
   secfile_insert_int(file, game.nuclearwinter, "game.nuclearwinter");
   secfile_insert_int(file, game.coolinglevel, "game.coolinglevel");
+  secfile_insert_int(file, game.fulltradesize, "game.fulltradesize");
   secfile_insert_int(file, game.unhappysize, "game.unhappysize");
   secfile_insert_int(file, game.angrycitizen, "game.angrycitizen");
   secfile_insert_int(file, game.cityfactor, "game.cityfactor");
diff -Nur -Xp1/diff_ignore orig/server/stdinhand.c p1/server/stdinhand.c
--- orig/server/stdinhand.c	Sun Sep 16 22:27:55 2001
+++ p1/server/stdinhand.c	Wed Oct 10 19:08:25 2001
@@ -489,7 +489,17 @@
     N_("If a city would expand, but it can't because it needs an Aqueduct "
        "(or Sewer System), it loses this percentage of its foodbox "
        "(or half that amount if it has a Granary).") },
-  
+
+  { "fulltradesize", &game.fulltradesize, NULL, NULL,
+    SSET_RULES, SSET_TO_CLIENT,
+    GAME_MIN_FULLTRADESIZE, GAME_MAX_FULLTRADESIZE, GAME_DEFAULT_FULLTRADESIZE,
+    N_("Minimum city size to get full trade"),
+    N_("There is a trade penalty in all cities smaller than this.  "
+       "The penalty is 100% (no trade at all) for sizes up to "
+       "fulltradesize/3, and decreases gradually to 0% (no penalty except the "
+       "normal corruption) for size=fulltradesize.  This does not apply under "
+       "Democracy.") },
+
   { "unhappysize", &game.unhappysize, NULL, NULL,
     SSET_RULES, SSET_TO_CLIENT,
     GAME_MIN_UNHAPPYSIZE, GAME_MAX_UNHAPPYSIZE, GAME_DEFAULT_UNHAPPYSIZE,