diff --git a/main.lua b/main.lua
index a671c69..c48bd62 100644
--- a/main.lua
+++ b/main.lua
@@ -70,11 +70,9 @@ end
 
 local world = World()
 
-local entity = Entity()
+local entity = Entity(world)
 entity:give(test_comp_1, 100, 100)
 
-world:addEntity(entity)
-
 world:addSystem(test_system_1, "test")
 world:addSystem(test_system_2, "test")
 
diff --git a/src/entity.lua b/src/entity.lua
index 755e75e..ff60a66 100644
--- a/src/entity.lua
+++ b/src/entity.lua
@@ -9,7 +9,11 @@ Entity.__index = Entity
 
 --- Creates and initializes a new Entity.
 -- @return A new Entity
-function Entity.new()
+function Entity.new(world)
+   if (world ~= nil and not Type.isWorld(world)) then
+      error("bad argument #1 to 'Entity.new' (world/nil expected, got "..type(world)..")", 2)
+   end
+
    local e = setmetatable({
       __world      = nil,
       __components = {},
@@ -17,6 +21,10 @@ function Entity.new()
       __isEntity = true,
    }, Entity)
 
+   if (world) then
+      world:addEntity(e)
+   end
+
    return e
 end