diff --git a/advtrains/advtrains/atc.lua b/advtrains/advtrains/atc.lua
index bd02425..e015d47 100644
--- a/advtrains/advtrains/atc.lua
+++ b/advtrains/advtrains/atc.lua
@@ -2,37 +2,10 @@
 --registers and controls the ATC system
 
 local atc={}
--- ATC persistence table
-atc.controllers = {}
+-- ATC persistence table. advtrains.atc is created by init.lua when it loads the save file.
+atc.controllers = advtrains.atc.controllers
 --contents: {command="...", arrowconn=0-15 where arrow points}
 
-advtrains.fpath_atc=minetest.get_worldpath().."/advtrains_atc"
-local file, err = io.open(advtrains.fpath_atc, "r")
-if not file then
-	local er=err or "Unknown Error"
-	atprint("Failed loading advtrains atc save file "..er)
-else
-	local tbl = minetest.deserialize(file:read("*a"))
-	if type(tbl) == "table" then
-		atc.controllers=tbl.controllers
-	end
-	file:close()
-end
-function atc.save()
-	--leave space for more save data.
-	local datastr = minetest.serialize({controllers = atc.controllers})
-	if not datastr then
-		minetest.log("error", " Failed to serialize trackdb data!")
-		return
-	end
-	local file, err = io.open(advtrains.fpath_atc, "w")
-	if err then
-		return err
-	end
-	file:write(datastr)
-	file:close()
-end
-
 --call from advtrains.detector subprogram
 
 function atc.trigger_controller_train_enter(pos, train_id)
@@ -290,5 +263,7 @@ function atc.execute_atc_command(id, train)
 	atc.train_reset_command(id)
 end
 
+
+
 --move table to desired place
 advtrains.atc=atc
diff --git a/advtrains/advtrains/init.lua b/advtrains/advtrains/init.lua
index a415857..74201b5 100644
--- a/advtrains/advtrains/init.lua
+++ b/advtrains/advtrains/init.lua
@@ -1,6 +1,7 @@
 --advtrains
 
-advtrains={}
+--create the base table structure.
+advtrains={atc={controllers={}}, detector={}, trackplacer={}, trains={}, trackdb={}, wagon_save={}}
 
 advtrains.modpath = minetest.get_modpath("advtrains")
 
@@ -34,8 +35,8 @@ local function print_concat_table(a)
 	end
 	return str
 end
-atprint=function() end
---atprint=function(t, ...) minetest.log("action", "[advtrains]"..print_concat_table({t, ...})) minetest.chat_send_all("[advtrains]"..print_concat_table({t, ...})) end
+--atprint=function() end
+atprint=function(t, ...) minetest.log("action", "[advtrains]"..print_concat_table({t, ...})) minetest.chat_send_all("[advtrains]"..print_concat_table({t, ...})) end
 sid=function(id) return string.sub(id, -4) end
 
 dofile(advtrains.modpath.."/helpers.lua");
@@ -55,6 +56,110 @@ advtrains.meseconrules =
  {x=0,  y=1,  z=-1},
  {x=0,  y=-1, z=-1},
  {x=0, y=-2, z=0}}
+ 
+
+
+--load/save
+
+advtrains.fpath=minetest.get_worldpath().."/advtrains"
+local file, err = io.open(advtrains.fpath, "r")
+if not file then
+	minetest.log("error", " Failed to read advtrains save data from file "..advtrains.fpath..": "..(err or "Unknown Error"))
+else
+	local tbl = minetest.deserialize(file:read("*a"))
+	if type(tbl) == "table" then
+		if tbl.version then
+			--congrats, we have the new save format.
+			advtrains.atc.controllers = tbl.atc_controllers
+			advtrains.trains = tbl.trains
+			advtrains.wagon_save = tbl.wagon_save
+		else
+			--oh no, its the old one...
+			advtrains.trains=tbl
+			--load ATC
+			advtrains.fpath_atc=minetest.get_worldpath().."/advtrains_atc"
+			local file, err = io.open(advtrains.fpath_atc, "r")
+			if not file then
+				local er=err or "Unknown Error"
+				atprint("Failed loading advtrains atc save file "..er)
+			else
+				local tbl = minetest.deserialize(file:read("*a"))
+				if type(tbl) == "table" then
+					advtrains.atc.controllers=tbl.controllers
+				end
+				file:close()
+			end
+			--load wagon saves
+			advtrains.fpath_ws=minetest.get_worldpath().."/advtrains_wagon_save"
+			local file, err = io.open(advtrains.fpath_ws, "r")
+			if not file then
+				local er=err or "Unknown Error"
+				atprint("Failed loading advtrains save file "..er)
+			else
+				local tbl = minetest.deserialize(file:read("*a"))
+				if type(tbl) == "table" then
+					advtrains.wagon_save=tbl
+				end
+				file:close()
+			end
+		end
+	else
+		minetest.log("error", " Failed to deserialize advtrains save data: Not a table!")
+	end
+	file:close()
+end
+
+advtrains.save = function()
+	atprint("saving")
+	advtrains.invalidate_all_paths()
+	
+	-- update wagon saves
+	for _,wagon in pairs(minetest.luaentities) do
+		if wagon.is_wagon and wagon.initialized then
+			wagon:get_staticdata()
+		end
+	end
+	--cross out userdata
+	for w_id, data in pairs(advtrains.wagon_save) do
+		data.name=nil
+		data.object=nil
+		if data.driver then
+			data.driver_name=data.driver:get_player_name()
+			data.driver=nil
+		else
+			data.driver_name=nil
+		end
+		if data.discouple then
+			data.discouple.object:remove()
+			data.discouple=nil
+		end
+	end
+	--atprint(dump(advtrains.wagon_save))
+	
+	--versions:
+	-- 1 - Initial new save format.
+	local save_tbl={
+		trains = advtrains.trains,
+		wagon_save = advtrains.wagon_save,
+		atc_controllers = advtrains.atc.controllers,
+		version = 1,
+	}
+	local datastr = minetest.serialize(save_tbl)
+	if not datastr then
+		minetest.log("error", " Failed to serialize advtrains save data!")
+		return
+	end
+	local file, err = io.open(advtrains.fpath, "w")
+	if err then
+		minetest.log("error", " Failed to write advtrains save data to file "..advtrains.fpath..": "..(err or "Unknown Error"))
+		return
+	end
+	file:write(datastr)
+	file:close()
+end
+minetest.register_on_shutdown(advtrains.save)
+
+
 dofile(advtrains.modpath.."/trainlogic.lua")
 dofile(advtrains.modpath.."/trainhud.lua")
 dofile(advtrains.modpath.."/trackplacer.lua")
@@ -69,3 +174,4 @@ dofile(advtrains.modpath.."/damage.lua")
 dofile(advtrains.modpath.."/signals.lua")
 dofile(advtrains.modpath.."/misc_nodes.lua")
 dofile(advtrains.modpath.."/crafting.lua")
+
diff --git a/advtrains/advtrains/pseudoload.lua b/advtrains/advtrains/pseudoload.lua
index 5cbd2c6..818808d 100644
--- a/advtrains/advtrains/pseudoload.lua
+++ b/advtrains/advtrains/pseudoload.lua
@@ -98,7 +98,8 @@ function advtrains.save_trackdb()
 	end
 end
 ]]--end temp outcomment
-advtrains.trackdb={}
+
+--trackdb keeps its own save file.
 advtrains.fpath_tdb=minetest.get_worldpath().."/advtrains_trackdb2"
 local file, err = io.open(advtrains.fpath_tdb, "r")
 if not file then
diff --git a/advtrains/advtrains/trainlogic.lua b/advtrains/advtrains/trainlogic.lua
index 07a48cc..c9c7403 100644
--- a/advtrains/advtrains/trainlogic.lua
+++ b/advtrains/advtrains/trainlogic.lua
@@ -39,96 +39,11 @@ advtrains.train_emerg_force=10--for emergency brakes(when going off track)
 advtrains.audit_interval=10
 
 
-advtrains.trains={}
-advtrains.wagon_save={}
-
---load initially
-advtrains.fpath=minetest.get_worldpath().."/advtrains"
-local file, err = io.open(advtrains.fpath, "r")
-if not file then
-	local er=err or "Unknown Error"
-	atprint("Failed loading advtrains save file "..er)
-else
-	local tbl = minetest.deserialize(file:read("*a"))
-	if type(tbl) == "table" then
-		advtrains.trains=tbl
-	end
-	file:close()
-end
-advtrains.fpath_ws=minetest.get_worldpath().."/advtrains_wagon_save"
-local file, err = io.open(advtrains.fpath_ws, "r")
-if not file then
-	local er=err or "Unknown Error"
-	atprint("Failed loading advtrains save file "..er)
-else
-	local tbl = minetest.deserialize(file:read("*a"))
-	if type(tbl) == "table" then
-		advtrains.wagon_save=tbl
-	end
-	file:close()
-end
-
-
-advtrains.save = function()
-	atprint("saving")
-	advtrains.invalidate_all_paths()
-	local datastr = minetest.serialize(advtrains.trains)
-	if not datastr then
-		minetest.log("error", " Failed to serialize train data!")
-		return
-	end
-	local file, err = io.open(advtrains.fpath, "w")
-	if err then
-		return err
-	end
-	file:write(datastr)
-	file:close()
-	
-	-- update wagon saves
-	for _,wagon in pairs(minetest.luaentities) do
-		if wagon.is_wagon and wagon.initialized then
-			wagon:get_staticdata()
-		end
-	end
-	--cross out userdata
-	for w_id, data in pairs(advtrains.wagon_save) do
-		data.name=nil
-		data.object=nil
-		if data.driver then
-			data.driver_name=data.driver:get_player_name()
-			data.driver=nil
-		else
-			data.driver_name=nil
-		end
-		if data.discouple then
-			data.discouple.object:remove()
-			data.discouple=nil
-		end
-	end
-	--atprint(dump(advtrains.wagon_save))
-	datastr = minetest.serialize(advtrains.wagon_save)
-	if not datastr then
-		minetest.log("error", " Failed to serialize train data!")
-		return
-	end
-	file, err = io.open(advtrains.fpath_ws, "w")
-	if err then
-		return err
-	end
-	file:write(datastr)
-	file:close()
-	
-	advtrains.save_trackdb()
-	advtrains.atc.save()
-end
-minetest.register_on_shutdown(advtrains.save)
-
 advtrains.save_and_audit_timer=advtrains.audit_interval
 minetest.register_globalstep(function(dtime)
 	advtrains.save_and_audit_timer=advtrains.save_and_audit_timer-dtime
 	if advtrains.save_and_audit_timer<=0 then
 		local t=os.clock()
-		
 		--save
 		advtrains.save()
 		advtrains.save_and_audit_timer=advtrains.audit_interval