diff --git a/LUA_API.rst b/LUA_API.rst
index fc86070c3..df997008c 100644
--- a/LUA_API.rst
+++ b/LUA_API.rst
@@ -699,6 +699,10 @@ Units module
 Items module
 ------------
 
+* ``dfhack.items.getPosition(item)``
+
+  Returns true *x,y,z* of the item.
+
 * ``dfhack.items.getOwner(item)``
 
   Returns the owner unit or *nil*.
@@ -708,6 +712,22 @@ Items module
   Replaces the owner of the item. If unit is *nil*, removes ownership.
   Returns *false* in case of error.
 
+* ``dfhack.items.getContainer(item)``
+
+  Returns the container item or *nil*.
+
+* ``dfhack.items.getContainedItems(item)``
+
+  Returns a list of items contained in this one.
+
+* ``dfhack.items.moveToGround(item,pos)``
+
+  Move the item to the ground at position. Returns *false* if impossible.
+
+* ``dfhack.items.moveToContainer(item,container)``
+
+  Move the item to the container. Returns *false* if impossible.
+
 
 Maps module
 -----------
diff --git a/Lua API.html b/Lua API.html
index 7c3eeddb9..4be1050fb 100644
--- a/Lua API.html	
+++ b/Lua API.html	
@@ -929,6 +929,9 @@ a lua list containing them.</p>
 <div class="section" id="items-module">
 <h3><a class="toc-backref" href="#id17">Items module</a></h3>
 <ul>
+<li><p class="first"><tt class="docutils literal">dfhack.items.getPosition(item)</tt></p>
+<p>Returns true <em>x,y,z</em> of the item.</p>
+</li>
 <li><p class="first"><tt class="docutils literal">dfhack.items.getOwner(item)</tt></p>
 <p>Returns the owner unit or <em>nil</em>.</p>
 </li>
@@ -936,6 +939,18 @@ a lua list containing them.</p>
 <p>Replaces the owner of the item. If unit is <em>nil</em>, removes ownership.
 Returns <em>false</em> in case of error.</p>
 </li>
+<li><p class="first"><tt class="docutils literal">dfhack.items.getContainer(item)</tt></p>
+<p>Returns the container item or <em>nil</em>.</p>
+</li>
+<li><p class="first"><tt class="docutils literal">dfhack.items.getContainedItems(item)</tt></p>
+<p>Returns a list of items contained in this one.</p>
+</li>
+<li><p class="first"><tt class="docutils literal">dfhack.items.moveToGround(item,pos)</tt></p>
+<p>Move the item to the ground at position. Returns <em>false</em> if impossible.</p>
+</li>
+<li><p class="first"><tt class="docutils literal">dfhack.items.moveToContainer(item,container)</tt></p>
+<p>Move the item to the container. Returns <em>false</em> if impossible.</p>
+</li>
 </ul>
 </div>
 <div class="section" id="maps-module">
diff --git a/library/LuaApi.cpp b/library/LuaApi.cpp
index febc59026..25f654b8c 100644
--- a/library/LuaApi.cpp
+++ b/library/LuaApi.cpp
@@ -45,6 +45,7 @@ distribution.
 #include "modules/Items.h"
 #include "modules/Materials.h"
 #include "modules/Maps.h"
+#include "modules/MapCache.h"
 
 #include "LuaWrapper.h"
 #include "LuaTools.h"
@@ -85,6 +86,33 @@ void push_pointer_vector(lua_State *state, const std::vector<T*> &pvec)
     }
 }
 
+template<class T>
+T *get_checked_arg(lua_State *state, int arg)
+{
+    luaL_checkany(state, arg);
+
+    auto ptr = Lua::GetDFObject<T>(state, arg);
+    if (!ptr)
+        luaL_argerror(state, arg, "invalid type");
+    return ptr;
+}
+
+int push_pos(lua_State *state, df::coord pos)
+{
+    if (!pos.isValid())
+    {
+        lua_pushnil(state);
+        return 1;
+    }
+    else
+    {
+        lua_pushinteger(state, pos.x);
+        lua_pushinteger(state, pos.y);
+        lua_pushinteger(state, pos.z);
+        return 3;
+    }
+}
+
 /**************************************************
  * Per-world persistent configuration storage API *
  **************************************************/
@@ -610,12 +638,47 @@ static const LuaWrapper::FunctionReg dfhack_units_module[] = {
     { NULL, NULL }
 };
 
+static bool items_moveToGround(df::item *item, df::coord pos)
+{
+    MapExtras::MapCache mc;
+    return Items::moveToGround(mc, item, pos);
+}
+
+static bool items_moveToContainer(df::item *item, df::item *container)
+{
+    MapExtras::MapCache mc;
+    return Items::moveToContainer(mc, item, container);
+}
+
 static const LuaWrapper::FunctionReg dfhack_items_module[] = {
     WRAPM(Items, getOwner),
     WRAPM(Items, setOwner),
+    WRAPM(Items, getContainer),
+    WRAPN(moveToGround, items_moveToGround),
+    WRAPN(moveToContainer, items_moveToContainer),
     { NULL, NULL }
 };
 
+static int items_getPosition(lua_State *state)
+{
+    return push_pos(state, Items::getPosition(get_checked_arg<df::item>(state,1)));
+}
+
+static int items_getContainedItems(lua_State *state)
+{
+    std::vector<df::item*> pvec;
+    Items::getContainedItems(get_checked_arg<df::item>(state,1),&pvec);
+    push_pointer_vector(state, pvec);
+    return 1;
+}
+
+static const luaL_Reg dfhack_items_funcs[] = {
+    { "getPosition", items_getPosition },
+    { "getContainedItems", items_getContainedItems },
+    { NULL, NULL }
+};
+
+
 static bool maps_isBlockBurrowTile(df::burrow *burrow, df::map_block *block, int x, int y)
 {
     return Maps::isBlockBurrowTile(burrow, block, df::coord2d(x,y));
@@ -642,14 +705,8 @@ static const LuaWrapper::FunctionReg dfhack_maps_module[] = {
 
 static int maps_listBurrowBlocks(lua_State *state)
 {
-    luaL_checkany(state, 1);
-
-    auto ptr = Lua::GetDFObject<df::burrow>(state, 1);
-    if (!ptr)
-        luaL_argerror(state, 1, "invalid burrow type");
-
     std::vector<df::map_block*> pvec;
-    Maps::listBurrowBlocks(&pvec, ptr);
+    Maps::listBurrowBlocks(&pvec, get_checked_arg<df::burrow>(state,1));
     push_pointer_vector(state, pvec);
     return 1;
 }
@@ -673,6 +730,6 @@ void OpenDFHackApi(lua_State *state)
     OpenModule(state, "gui", dfhack_gui_module);
     OpenModule(state, "job", dfhack_job_module, dfhack_job_funcs);
     OpenModule(state, "units", dfhack_units_module);
-    OpenModule(state, "items", dfhack_items_module);
+    OpenModule(state, "items", dfhack_items_module, dfhack_items_funcs);
     OpenModule(state, "maps", dfhack_maps_module, dfhack_maps_funcs);
 }
diff --git a/library/include/modules/Items.h b/library/include/modules/Items.h
index 9bab02cc8..e7720fa91 100644
--- a/library/include/modules/Items.h
+++ b/library/include/modules/Items.h
@@ -42,6 +42,10 @@ namespace df
     struct itemdef;
 }
 
+namespace MapExtras {
+    class MapCache;
+}
+
 /**
  * \defgroup grp_items Items module and its types
  * @ingroup grp_modules
@@ -128,13 +132,15 @@ DFHACK_EXPORT df::unit *getOwner(df::item *item);
 DFHACK_EXPORT bool setOwner(df::item *item, df::unit *unit);
 
 /// which item is it contained in?
-DFHACK_EXPORT int32_t getItemContainerID(const df::item * item);
-DFHACK_EXPORT df::item *getItemContainer(const df::item * item);
+DFHACK_EXPORT df::item *getContainer(df::item *item);
 /// which items does it contain?
-DFHACK_EXPORT bool getContainedItems(const df::item * item, /*output*/ std::vector<int32_t> &items);
+DFHACK_EXPORT void getContainedItems(df::item *item, /*output*/ std::vector<df::item*> *items);
+
+/// Returns the true position of the item.
+DFHACK_EXPORT df::coord getPosition(df::item *item);
+
+DFHACK_EXPORT bool moveToGround(MapExtras::MapCache &mc, df::item *item, df::coord pos);
+DFHACK_EXPORT bool moveToContainer(MapExtras::MapCache &mc, df::item *item, df::item *container);
 
-/// read item references, filtered by class
-DFHACK_EXPORT bool readItemRefs(const df::item * item, const df::general_ref_type type,
-                  /*output*/ std::vector<int32_t> &values);
 }
 }
\ No newline at end of file
diff --git a/library/lua/dfhack.lua b/library/lua/dfhack.lua
index a6606d152..626f60bec 100644
--- a/library/lua/dfhack.lua
+++ b/library/lua/dfhack.lua
@@ -86,6 +86,21 @@ function copyall(table)
     return rv
 end
 
+function pos2xyz(pos)
+    local x = pos.x
+    if x and x ~= -30000 then
+        return x, pos.y, pos.z
+    end
+end
+
+function xyz2pos(x,y,z)
+    if x then
+        return {x=x,y=y,z=z}
+    else
+        return {x=-30000,y=-30000,z=-30000}
+    end
+end
+
 function dfhack.persistent:__tostring()
     return "<persistent "..self.entry_id..":"..self.key.."=\""
            ..self.value.."\":"..table.concat(self.ints,",")..">"
diff --git a/library/modules/Items.cpp b/library/modules/Items.cpp
index 20b95bc23..ca15ed278 100644
--- a/library/modules/Items.cpp
+++ b/library/modules/Items.cpp
@@ -39,6 +39,7 @@ using namespace std;
 #include "modules/Materials.h"
 #include "modules/Items.h"
 #include "modules/Units.h"
+#include "modules/MapCache.h"
 #include "ModuleFactory.h"
 #include "Core.h"
 #include "Error.h"
@@ -46,6 +47,7 @@ using namespace std;
 
 #include "df/world.h"
 #include "df/item.h"
+#include "df/building.h"
 #include "df/tool_uses.h"
 #include "df/itemdef_weaponst.h"
 #include "df/itemdef_trapcompst.h"
@@ -65,6 +67,8 @@ using namespace std;
 #include "df/job_item.h"
 #include "df/general_ref.h"
 #include "df/general_ref_unit_itemownerst.h"
+#include "df/general_ref_contains_itemst.h"
+#include "df/general_ref_contained_in_itemst.h"
 
 using namespace DFHack;
 using namespace df::enums;
@@ -472,44 +476,183 @@ bool Items::setOwner(df::item *item, df::unit *unit)
     return true;
 }
 
-
-int32_t Items::getItemContainerID(const df::item * item)
+df::item *Items::getContainer(df::item * item)
 {
+    CHECK_NULL_POINTER(item);
+
     for (size_t i = 0; i < item->itemrefs.size(); i++)
     {
         df::general_ref *ref = item->itemrefs[i];
         if (ref->getType() == general_ref_type::CONTAINED_IN_ITEM)
-            return ref->getID();
+            return ref->getItem();
     }
-    return -1;
+
+    return NULL;
 }
 
-df::item *Items::getItemContainer(const df::item * item)
+void Items::getContainedItems(df::item *item, std::vector<df::item*> *items)
 {
+    CHECK_NULL_POINTER(item);
+
+    items->clear();
+
     for (size_t i = 0; i < item->itemrefs.size(); i++)
     {
         df::general_ref *ref = item->itemrefs[i];
-        if (ref->getType() == general_ref_type::CONTAINED_IN_ITEM)
-            return ref->getItem();
+        if (ref->getType() != general_ref_type::CONTAINS_ITEM)
+            continue;
+
+        auto child = ref->getItem();
+        if (child)
+            items->push_back(child);
     }
-    return NULL;
 }
 
-bool Items::getContainedItems(const df::item * item, std::vector<int32_t> &items)
+df::coord Items::getPosition(df::item *item)
 {
-    return readItemRefs(item, general_ref_type::CONTAINS_ITEM, items);
+    CHECK_NULL_POINTER(item);
+
+    if (item->flags.bits.in_inventory ||
+        item->flags.bits.in_chest ||
+        item->flags.bits.in_building)
+    {
+        for (size_t i = 0; i < item->itemrefs.size(); i++)
+        {
+            df::general_ref *ref = item->itemrefs[i];
+
+            switch (ref->getType())
+            {
+            case general_ref_type::CONTAINED_IN_ITEM:
+                if (auto item2 = ref->getItem())
+                    return getPosition(item2);
+                break;
+
+            case general_ref_type::UNIT_HOLDER:
+                if (auto unit = ref->getUnit())
+                    return unit->pos;
+                break;
+
+            case general_ref_type::BUILDING_HOLDER:
+                if (auto bld = ref->getBuilding())
+                    return df::coord(bld->centerx, bld->centery, bld->z);
+                break;
+            }
+        }
+    }
+
+    return item->pos;
 }
 
-bool Items::readItemRefs(const df::item * item, df::general_ref_type type, std::vector<int32_t> &values)
+static void removeRef(std::vector<df::general_ref*> &vec, df::general_ref_type type, int id)
 {
-    values.clear();
+    for (int i = vec.size()-1; i >= 0; i--)
+    {
+        df::general_ref *ref = vec[i];
+        if (ref->getType() != type || ref->getID() != id)
+            continue;
 
-    for (size_t i = 0; i < item->itemrefs.size(); i++)
+        vector_erase_at(vec, i);
+        delete ref;
+    }
+}
+
+static bool detachItem(MapExtras::MapCache &mc, df::item *item)
+{
+    if (item->flags.bits.on_ground)
     {
-        df::general_ref *ref = item->itemrefs[i];
-        if (ref->getType() == type)
-            values.push_back(ref->getID());
+        if (!mc.removeItemOnGround(item))
+            Core::printerr("Item was marked on_ground, but not in block: %d (%d,%d,%d)\n",
+                           item->id, item->pos.x, item->pos.y, item->pos.z);
+
+        item->flags.bits.on_ground = false;
+        return true;
     }
+    else if (item->flags.bits.in_inventory)
+    {
+        bool found = false;
 
-    return !values.empty();
+        for (int i = item->itemrefs.size()-1; i >= 0; i--)
+        {
+            df::general_ref *ref = item->itemrefs[i];
+
+            switch (ref->getType())
+            {
+            case general_ref_type::CONTAINED_IN_ITEM:
+                if (auto item2 = ref->getItem())
+                    removeRef(item2->itemrefs, general_ref_type::CONTAINS_ITEM, item->id);
+                break;
+
+            case general_ref_type::UNIT_HOLDER:
+            case general_ref_type::BUILDING_HOLDER:
+                return false;
+
+            default:
+                continue;
+            }
+
+            found = true;
+            vector_erase_at(item->itemrefs, i);
+            delete ref;
+        }
+
+        if (!found)
+            return false;
+
+        item->flags.bits.in_inventory = false;
+        return true;
+    }
+    else
+        return false;
+}
+
+static void putOnGround(MapExtras::MapCache &mc, df::item *item, df::coord pos)
+{
+    item->pos = pos;
+    item->flags.bits.on_ground = true;
+
+    if (!mc.addItemOnGround(item))
+        Core::printerr("Could not add item %d to ground at (%d,%d,%d)\n",
+                       item->id, pos.x, pos.y, pos.z);
+}
+
+bool DFHack::Items::moveToGround(MapExtras::MapCache &mc, df::item *item, df::coord pos)
+{
+    CHECK_NULL_POINTER(item);
+
+    if (!detachItem(mc, item))
+        return false;
+
+    putOnGround(mc, item, pos);
+    return true;
+}
+
+bool DFHack::Items::moveToContainer(MapExtras::MapCache &mc, df::item *item, df::item *container)
+{
+    CHECK_NULL_POINTER(item);
+    CHECK_NULL_POINTER(container);
+
+    if (!detachItem(mc, item))
+        return false;
+
+    auto ref1 = df::allocate<df::general_ref_contains_itemst>();
+    auto ref2 = df::allocate<df::general_ref_contained_in_itemst>();
+
+    if (!ref1 || !ref2)
+    {
+        delete ref1; delete ref2;
+        Core::printerr("Could not allocate container refs.\n");
+        putOnGround(mc, item, getPosition(container));
+        return false;
+    }
+
+    item->pos = container->pos;
+    item->flags.bits.in_inventory = true;
+    container->flags.bits.container = true;
+
+    ref1->item_id = item->id;
+    container->itemrefs.push_back(ref1);
+    ref2->item_id = container->id;
+    item->itemrefs.push_back(ref2);
+
+    return true;
 }
diff --git a/library/modules/Maps.cpp b/library/modules/Maps.cpp
index c0aa9b634..fce80d775 100644
--- a/library/modules/Maps.cpp
+++ b/library/modules/Maps.cpp
@@ -596,7 +596,7 @@ void MapExtras::Block::init_item_counts()
     if (item_counts) return;
 
     item_counts = new T_item_counts[16];
-    memset(item_counts, 0, sizeof(T_item_counts));
+    memset(item_counts, 0, sizeof(T_item_counts)*16);
 
     if (!block) return;
 
diff --git a/plugins/autodump.cpp b/plugins/autodump.cpp
index a71555b7a..2620d9dea 100644
--- a/plugins/autodump.cpp
+++ b/plugins/autodump.cpp
@@ -182,15 +182,7 @@ static command_result autodump_main(color_ostream &out, vector <string> & parame
 
             // Don't move items if they're already at the cursor
             if (pos_cursor != pos_item)
-            {
-                if (!MC.removeItemOnGround(itm))
-                    out.printerr("Item %d wasn't in the source block.\n", itm->id);
-
-                itm->pos = pos_cursor;
-
-                if (!MC.addItemOnGround(itm))
-                    out.printerr("Could not add item %d to destination block.\n", itm->id);
-            }
+                Items::moveToGround(MC, itm, pos_cursor);
         }
         else // destroy
         {