diff --git a/docs/dev/Lua API.rst b/docs/dev/Lua API.rst
index 08b20e1b3..f29df78c6 100644
--- a/docs/dev/Lua API.rst	
+++ b/docs/dev/Lua API.rst	
@@ -1525,6 +1525,11 @@ Units module
 
   Computes the effective attribute value, including curse effect.
 
+* ``dfhack.units.casteFlagSet(race, caste, flag)``
+
+  Returns whether the given ``df.caste_raw_flags`` flag is set for the given
+  race and caste.
+
 * ``dfhack.units.getMiscTrait(unit, type[, create])``
 
   Finds (or creates if requested) a misc trait object with the given id.
diff --git a/library/LuaApi.cpp b/library/LuaApi.cpp
index 9dc86b526..beaf50579 100644
--- a/library/LuaApi.cpp
+++ b/library/LuaApi.cpp
@@ -1816,6 +1816,7 @@ static const LuaWrapper::FunctionReg dfhack_units_module[] = {
     WRAPM(Units, getNemesis),
     WRAPM(Units, getPhysicalAttrValue),
     WRAPM(Units, getMentalAttrValue),
+    WRAPM(Units, casteFlagSet),
     WRAPM(Units, getMiscTrait),
     WRAPM(Units, getAge),
     WRAPM(Units, getKillCount),
diff --git a/plugins/lua/zone.lua b/plugins/lua/zone.lua
index b30ba3a5c..29859e419 100644
--- a/plugins/lua/zone.lua
+++ b/plugins/lua/zone.lua
@@ -450,7 +450,9 @@ end
 
 local function get_unit_disposition(unit)
     local disposition = DISPOSITION.NONE
-    if dfhack.units.isPet(unit) then
+    if dfhack.units.isInvader(unit) or dfhack.units.isOpposedToLife(unit) then
+        disposition = DISPOSITION.HOSTILE
+    elseif dfhack.units.isPet(unit) then
         disposition = DISPOSITION.PET
     elseif dfhack.units.isDomesticated(unit) then
         disposition = DISPOSITION.TAME
@@ -458,8 +460,6 @@ local function get_unit_disposition(unit)
         disposition = DISPOSITION.TRAINED
     elseif dfhack.units.isTamable(unit) then
         disposition = DISPOSITION.WILD_TRAINABLE
-    elseif dfhack.units.isInvader(unit) or dfhack.units.isOpposedToLife(unit) then
-        disposition = DISPOSITION.HOSTILE
     else
         disposition = DISPOSITION.WILD_UNTRAINABLE
     end
@@ -467,8 +467,21 @@ local function get_unit_disposition(unit)
 end
 
 local function get_item_disposition(item)
-    -- TODO
-    return DISPOSITION.TAME.value
+    local disposition = DISPOSITION.NONE
+    if dfhack.units.casteFlagSet(item.race, item.caste, df.caste_raw_flags.OPPOSED_TO_LIFE) then
+        disposition = DISPOSITION.HOSTILE
+    -- elseif dfhack.units.isPet(unit) then
+    --     disposition = DISPOSITION.PET
+    -- elseif dfhack.units.isDomesticated(unit) then
+    --     disposition = DISPOSITION.TAME
+    elseif dfhack.units.casteFlagSet(item.race, item.caste, df.caste_raw_flags.PET) or
+        dfhack.units.casteFlagSet(item.race, item.caste, df.caste_raw_flags.PET_EXOTIC)
+    then
+        disposition = DISPOSITION.WILD_TRAINABLE
+    else
+        disposition = DISPOSITION.WILD_UNTRAINABLE
+    end
+    return disposition.value
 end
 
 local function is_assignable_unit(unit)