diff --git a/models/browser_state.als b/models/browser_state.als
new file mode 100644
index 0000000..2adf814
--- /dev/null
+++ b/models/browser_state.als
@@ -0,0 +1,51 @@
+sig Id {}
+sig Text {}
+
+sig Recipe {
+ 	, id: one Id
+   , text: one Text
+} 
+
+fact {
+   no r1, r2: Recipe | (r1.id = r2.id) and (r1.text != r2.text)
+   no r1, r2: Recipe | (r1 != r2) and (r1.id = r2.id)
+}
+
+sig Ingredient {}
+sig Modifier {}
+sig Amt {}
+
+sig ModifiedInventory {
+    , ingredient: one Ingredient
+    , modifier: lone Modifier
+    , amt: one Amt
+}
+
+fact {
+   no mi1, mi2: ModifiedInventory | mi1 != mi2 && (mi1.ingredient = mi2.ingredient) and (mi1.modifier = mi2.modifier)
+}
+
+sig DeletedInventory {
+    , ingredient: one Ingredient
+    , modifier: lone Modifier
+}
+
+fact {
+   no mi1, mi2: DeletedInventory | mi1 != mi2 && (mi1.ingredient = mi2.ingredient) and (mi1.modifier = mi2.modifier)
+}
+
+sig ExtraItems {
+    , ingredient: one Ingredient
+    , amt: one Amt
+}
+
+sig State {
+	, recipes: some Recipe
+    , modified: set ModifiedInventory
+    , deleted: set DeletedInventory
+    , extras: set ExtraItems
+} {
+	no rs: Recipe | rs not in recipes
+}
+
+run { } for 3 but exactly 2 State, 2 Modifier, exactly 3 ModifiedInventory, exactly 9 Ingredient