diff --git a/aisleriot/game.c b/aisleriot/game.c
index 7245c25..38e2c0e 100644
--- a/aisleriot/game.c
+++ b/aisleriot/game.c
@@ -569,6 +569,8 @@ cscmi_add_slot (SCM slot_data)
   gboolean expanded_down = FALSE;
   gboolean expanded_right = FALSE;
   int expansion_depth = 0;
+  AisleriotSlotType type = AISLERIOT_SLOT_UNKNOWN;
+  SCM slot_placement, slot_type;
 
   if (game->state > GAME_BEGIN) {
     return scm_throw (scm_from_locale_symbol ("game-started"),
@@ -577,30 +579,53 @@ cscmi_add_slot (SCM slot_data)
   }
 
 #ifdef HAVE_GUILE_1_8
-#define CHECK_EXPANSION(string,object) (scm_is_true (scm_equal_p (scm_from_locale_symbol (string), object)))
+#define EQUALS_SYMBOL(string,object) (scm_is_true (scm_equal_p (scm_from_locale_symbol (string), object)))
 #else
-#define CHECK_EXPANSION(string,object) (!strcmp (string, SCM_CHARS (object)))
+#define EQUALS_SYMBOL(string,object) (!strcmp (string, SCM_CHARS (object)))
 #endif
 
-  if (CHECK_EXPANSION ("expanded", SCM_CAR (SCM_CADDR (slot_data)))) {
+  slot_placement = SCM_CADDR (slot_data);
+  if (EQUALS_SYMBOL ("expanded", SCM_CAR (slot_placement))) {
     expanded_down = TRUE;
-  } else if (CHECK_EXPANSION ("expanded-right", SCM_CAR (SCM_CADDR (slot_data)))) {
+  } else if (EQUALS_SYMBOL ("expanded-right", SCM_CAR (slot_placement))) {
     expanded_right = TRUE;
-  } else if (CHECK_EXPANSION ("partially-expanded", SCM_CAR (SCM_CADDR (slot_data)))) {
+  } else if (EQUALS_SYMBOL ("partially-expanded", SCM_CAR (slot_placement))) {
     expanded_down = TRUE;
-    expansion_depth = scm_to_int (SCM_CADDR (SCM_CADDR (slot_data)));
-  } else if (CHECK_EXPANSION ("partially-expanded-right", SCM_CAR (SCM_CADDR (slot_data)))) {
+    expansion_depth = scm_to_int (SCM_CADDR (slot_placement));
+  } else if (EQUALS_SYMBOL ("partially-expanded-right", SCM_CAR (slot_placement))) {
     expanded_right = TRUE;
-    expansion_depth = scm_to_int (SCM_CADDR (SCM_CADDR (slot_data)));
+    expansion_depth = scm_to_int (SCM_CADDR (slot_placement));
   }
 
-#undef CHECK_EXPANSION
+  /* 3rd argument is the slot type (optionally) */
+  slot_type = SCM_CDDDR (slot_data);
+  if (slot_type != SCM_EOL) {
+    if (EQUALS_SYMBOL ("foundation", SCM_CAR (slot_type))) {
+      type = AISLERIOT_SLOT_FOUNDATION;
+    } else if (EQUALS_SYMBOL ("reserve", SCM_CAR (slot_type))) {
+      type = AISLERIOT_SLOT_RESERVE;
+    } else if (EQUALS_SYMBOL ("stock", SCM_CAR (slot_type))) {
+      type = AISLERIOT_SLOT_STOCK;
+    } else if (EQUALS_SYMBOL ("tableau", SCM_CAR (slot_type))) {
+      type = AISLERIOT_SLOT_TABLEAU;
+    } else if (EQUALS_SYMBOL ("waste", SCM_CAR (slot_type))) {
+      type = AISLERIOT_SLOT_WASTE;
+    }
+  }
+
+#undef EQUALS_SYMBOL
+
+  {
+    static const char *types[] = { "unknown", "foundation", "reserve", "stock", "tableau", "waste" };
+    g_print ("add-slot ID %d type %s\n", scm_to_int (SCM_CAR (slot_data)), types[type]);
+  }
 
   /* create and initialize slot */
   slot = g_slice_new0 (Slot);
   g_ptr_array_add (game->slots, slot);
 
   slot->id = scm_to_int (SCM_CAR (slot_data));
+  slot->type = type;
 
   slot->cards = g_byte_array_sized_new (SLOT_CARDS_N_PREALLOC);
   slot->exposed = 0;
diff --git a/aisleriot/game.h b/aisleriot/game.h
index 541e34a..ba63bfa 100644
--- a/aisleriot/game.h
+++ b/aisleriot/game.h
@@ -29,10 +29,20 @@
 
 G_BEGIN_DECLS
 
+typedef enum {
+  AISLERIOT_SLOT_UNKNOWN,
+  AISLERIOT_SLOT_FOUNDATION,
+  AISLERIOT_SLOT_RESERVE,
+  AISLERIOT_SLOT_STOCK,
+  AISLERIOT_SLOT_TABLEAU,
+  AISLERIOT_SLOT_WASTE
+} AisleriotSlotType;
+
 /* A slot */
 
 typedef struct {
   int id;
+  AisleriotSlotType type;
 
   GByteArray *cards;
 #ifdef HAVE_CLUTTER
diff --git a/aisleriot/sol.scm b/aisleriot/sol.scm
index b60f9b2..b53f6de 100644
--- a/aisleriot/sol.scm
+++ b/aisleriot/sol.scm
@@ -163,8 +163,8 @@
 ; The real slots come in three varieties:
 ; A slot in which only the topmost card is visible:
 (define (add-normal-slot cards)
-  (add-slot (set-tag! (new-slot cards 
-				(list 'normal (get-and-increment-position))))))
+  (add-slot (set-tag! (new-slot cards
+				(list 'normal (get-and-increment-position)) 'unknown))))
 
 ; A slot in which all the cards are visible, arranged as an overlapped pile:
 ; (either proceeding to the right or down).
@@ -172,20 +172,20 @@
   (if (= right direction)
       (add-slot (set-tag! (new-slot cards 
 				    (list 'expanded-right 
-					  (get-and-increment-position)))))
+					  (get-and-increment-position)) 'unknown)))
       (add-slot (set-tag! (new-slot cards 
 				    (list 'expanded 
-					  (get-and-increment-position)))))))
+					  (get-and-increment-position)) 'unknown)))))
 
 ; A slot in only the n topmost cards are visible:
 (define (add-partially-extended-slot cards direction n)
   (if (= right direction)
       (add-slot (set-tag! (new-slot cards 
 				    (list 'partially-expanded-right 
-					  (get-and-increment-position) n))))
+					  (get-and-increment-position) n) 'unknown)))
       (add-slot (set-tag! (new-slot cards 
 				    (list 'partially-expanded 
-					  (get-and-increment-position) n))))))
+					  (get-and-increment-position) n) 'unknown)))))
 
 ; Cards may be dealt off one slot (usually the one containing the deck)
 ; and onto a list of other slots using these procedures:
@@ -516,8 +516,8 @@
 	(vector-set! deck ref2 (vector-ref deck ref1))
 	(shuffle-deck-helper deck (cons val-at-ref2 result) (+ ref1 1) (- len 1)))))
 
-(define (new-slot deck placement)
-  (list #f deck placement))
+(define (new-slot deck placement type)
+  (list #f deck placement type))
 
 (define (set-tag! slot)
   (set! SLOTS (+ 1 SLOTS))