diff --git a/src/blenderbim/blenderbim/bim/__init__.py b/src/blenderbim/blenderbim/bim/__init__.py
index 6f1531121c..d62f3e9e12 100644
--- a/src/blenderbim/blenderbim/bim/__init__.py
+++ b/src/blenderbim/blenderbim/bim/__init__.py
@@ -29,6 +29,7 @@ if bpy is not None:
         "cost": None,
         "sequence": None,
         "group": None,
+        "system": None,
         "structural": None,
         "boundary": None,
         "material": None,
diff --git a/src/blenderbim/blenderbim/bim/module/system/__init__.py b/src/blenderbim/blenderbim/bim/module/system/__init__.py
new file mode 100644
index 0000000000..0059a29f4d
--- /dev/null
+++ b/src/blenderbim/blenderbim/bim/module/system/__init__.py
@@ -0,0 +1,27 @@
+import bpy
+from . import ui, prop, operator
+
+classes = (
+    operator.LoadSystems,
+    operator.DisableSystemEditingUI,
+    operator.AddSystem,
+    operator.EditSystem,
+    operator.RemoveSystem,
+    operator.AssignSystem,
+    operator.UnassignSystem,
+    operator.EnableEditingSystem,
+    operator.DisableEditingSystem,
+    operator.SelectSystemProducts,
+    prop.System,
+    prop.BIMSystemProperties,
+    ui.BIM_PT_systems,
+    ui.BIM_UL_systems,
+)
+
+
+def register():
+    bpy.types.Scene.BIMSystemProperties = bpy.props.PointerProperty(type=prop.BIMSystemProperties)
+
+
+def unregister():
+    del bpy.types.Scene.BIMSystemProperties
diff --git a/src/blenderbim/blenderbim/bim/module/system/operator.py b/src/blenderbim/blenderbim/bim/module/system/operator.py
new file mode 100644
index 0000000000..da5a714f09
--- /dev/null
+++ b/src/blenderbim/blenderbim/bim/module/system/operator.py
@@ -0,0 +1,196 @@
+import bpy
+import ifcopenshell.util.attribute
+import ifcopenshell.api
+from blenderbim.bim.ifc import IfcStore
+from ifcopenshell.api.system.data import Data
+
+
+class LoadSystems(bpy.types.Operator):
+    bl_idname = "bim.load_systems"
+    bl_label = "Load Systems"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def execute(self, context):
+        props = context.scene.BIMSystemProperties
+        while len(props.systems) > 0:
+            props.systems.remove(0)
+        for ifc_definition_id, system in Data.systems.items():
+            new = props.systems.add()
+            new.ifc_definition_id = ifc_definition_id
+            new.name = system["Name"]
+        props.is_editing = True
+        bpy.ops.bim.disable_editing_system()
+        return {"FINISHED"}
+
+
+class DisableSystemEditingUI(bpy.types.Operator):
+    bl_idname = "bim.disable_system_editing_ui"
+    bl_label = "Disable System Editing UI"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def execute(self, context):
+        context.scene.BIMSystemProperties.is_editing = False
+        return {"FINISHED"}
+
+
+class AddSystem(bpy.types.Operator):
+    bl_idname = "bim.add_system"
+    bl_label = "Add System"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def execute(self, context):
+        return IfcStore.execute_ifc_operator(self, context)
+
+    def _execute(self, context):
+        result = ifcopenshell.api.run("system.add_system", IfcStore.get_file())
+        Data.load(IfcStore.get_file())
+        bpy.ops.bim.load_systems()
+        bpy.ops.bim.enable_editing_system(system=result.id())
+        return {"FINISHED"}
+
+
+class EditSystem(bpy.types.Operator):
+    bl_idname = "bim.edit_system"
+    bl_label = "Edit System"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def execute(self, context):
+        return IfcStore.execute_ifc_operator(self, context)
+
+    def _execute(self, context):
+        props = context.scene.BIMSystemProperties
+        attributes = {}
+        for attribute in props.system_attributes:
+            if attribute.is_null:
+                attributes[attribute.name] = None
+            else:
+                attributes[attribute.name] = attribute.string_value
+        self.file = IfcStore.get_file()
+        ifcopenshell.api.run(
+            "system.edit_system", self.file, **{"system": self.file.by_id(props.active_system_id), "attributes": attributes}
+        )
+        Data.load(IfcStore.get_file())
+        bpy.ops.bim.load_systems()
+        return {"FINISHED"}
+
+
+class RemoveSystem(bpy.types.Operator):
+    bl_idname = "bim.remove_system"
+    bl_label = "Remove System"
+    bl_options = {"REGISTER", "UNDO"}
+    system: bpy.props.IntProperty()
+
+    def execute(self, context):
+        return IfcStore.execute_ifc_operator(self, context)
+
+    def _execute(self, context):
+        props = context.scene.BIMSystemProperties
+        self.file = IfcStore.get_file()
+        ifcopenshell.api.run("system.remove_system", self.file, **{"system": self.file.by_id(self.system)})
+        Data.load(IfcStore.get_file())
+        bpy.ops.bim.load_systems()
+        return {"FINISHED"}
+
+
+class EnableEditingSystem(bpy.types.Operator):
+    bl_idname = "bim.enable_editing_system"
+    bl_label = "Enable Editing System"
+    bl_options = {"REGISTER", "UNDO"}
+    system: bpy.props.IntProperty()
+
+    def execute(self, context):
+        props = context.scene.BIMSystemProperties
+        while len(props.system_attributes) > 0:
+            props.system_attributes.remove(0)
+
+        data = Data.systems[self.system]
+
+        for attribute in IfcStore.get_schema().declaration_by_name("IfcSystem").all_attributes():
+            data_type = ifcopenshell.util.attribute.get_primitive_type(attribute)
+            if data_type == "entity":
+                continue
+            new = props.system_attributes.add()
+            new.name = attribute.name()
+            new.is_null = data[attribute.name()] is None
+            new.is_optional = attribute.optional()
+            new.string_value = "" if new.is_null else data[attribute.name()]
+        props.active_system_id = self.system
+        return {"FINISHED"}
+
+
+class DisableEditingSystem(bpy.types.Operator):
+    bl_idname = "bim.disable_editing_system"
+    bl_label = "Disable Editing System"
+    bl_options = {"REGISTER", "UNDO"}
+
+    def execute(self, context):
+        context.scene.BIMSystemProperties.active_system_id = 0
+        return {"FINISHED"}
+
+
+class AssignSystem(bpy.types.Operator):
+    bl_idname = "bim.assign_system"
+    bl_label = "Assign System"
+    bl_options = {"REGISTER", "UNDO"}
+    product: bpy.props.StringProperty()
+    system: bpy.props.IntProperty()
+
+    def execute(self, context):
+        return IfcStore.execute_ifc_operator(self, context)
+
+    def _execute(self, context):
+        product = bpy.data.objects.get(self.product) if self.product else context.active_object
+        self.file = IfcStore.get_file()
+        ifcopenshell.api.run(
+            "system.assign_system",
+            self.file,
+            **{
+                "product": self.file.by_id(product.BIMObjectProperties.ifc_definition_id),
+                "system": self.file.by_id(self.system),
+            }
+        )
+        Data.load(IfcStore.get_file())
+        return {"FINISHED"}
+
+
+class UnassignSystem(bpy.types.Operator):
+    bl_idname = "bim.unassign_system"
+    bl_label = "Unassign System"
+    bl_options = {"REGISTER", "UNDO"}
+    product: bpy.props.StringProperty()
+    system: bpy.props.IntProperty()
+
+    def execute(self, context):
+        return IfcStore.execute_ifc_operator(self, context)
+
+    def _execute(self, context):
+        product = bpy.data.objects.get(self.product) if self.product else context.active_object
+        self.file = IfcStore.get_file()
+        ifcopenshell.api.run(
+            "system.unassign_system",
+            self.file,
+            **{
+                "product": self.file.by_id(product.BIMObjectProperties.ifc_definition_id),
+                "system": self.file.by_id(self.system),
+            }
+        )
+        Data.load(IfcStore.get_file())
+        return {"FINISHED"}
+
+
+class SelectSystemProducts(bpy.types.Operator):
+    bl_idname = "bim.select_system_products"
+    bl_label = "Select System Products"
+    bl_options = {"REGISTER", "UNDO"}
+    system: bpy.props.IntProperty()
+
+    def execute(self, context):
+        self.file = IfcStore.get_file()
+        for obj in bpy.context.visible_objects:
+            obj.select_set(False)
+            if not obj.BIMObjectProperties.ifc_definition_id:
+                continue
+            product_systems = Data.products.get(obj.BIMObjectProperties.ifc_definition_id, [])
+            if self.system in product_systems:
+                obj.select_set(True)
+        return {"FINISHED"}
diff --git a/src/blenderbim/blenderbim/bim/module/system/prop.py b/src/blenderbim/blenderbim/bim/module/system/prop.py
new file mode 100644
index 0000000000..5bed5a3fd9
--- /dev/null
+++ b/src/blenderbim/blenderbim/bim/module/system/prop.py
@@ -0,0 +1,26 @@
+import bpy
+from blenderbim.bim.prop import StrProperty, Attribute
+from bpy.types import PropertyGroup
+from bpy.props import (
+    PointerProperty,
+    StringProperty,
+    EnumProperty,
+    BoolProperty,
+    IntProperty,
+    FloatProperty,
+    FloatVectorProperty,
+    CollectionProperty,
+)
+
+
+class System(PropertyGroup):
+    name: StringProperty(name="Name")
+    ifc_definition_id: IntProperty(name="IFC Definition ID")
+
+
+class BIMSystemProperties(PropertyGroup):
+    system_attributes: CollectionProperty(name="System Attributes", type=Attribute)
+    is_editing: BoolProperty(name="Is Editing", default=False)
+    systems: CollectionProperty(name="Systems", type=System)
+    active_system_index: IntProperty(name="Active System Index")
+    active_system_id: IntProperty(name="Active System Id")
diff --git a/src/blenderbim/blenderbim/bim/module/system/ui.py b/src/blenderbim/blenderbim/bim/module/system/ui.py
new file mode 100644
index 0000000000..067dd038fc
--- /dev/null
+++ b/src/blenderbim/blenderbim/bim/module/system/ui.py
@@ -0,0 +1,85 @@
+from bpy.types import Panel, UIList
+from blenderbim.bim.ifc import IfcStore
+from ifcopenshell.api.system.data import Data
+
+
+class BIM_PT_systems(Panel):
+    bl_label = "IFC Systems"
+    bl_idname = "BIM_PT_systems"
+    bl_options = {"DEFAULT_CLOSED"}
+    bl_space_type = "PROPERTIES"
+    bl_region_type = "WINDOW"
+    bl_context = "scene"
+
+    @classmethod
+    def poll(cls, context):
+        return IfcStore.get_file()
+
+    def draw(self, context):
+        if not Data.is_loaded:
+            Data.load(IfcStore.get_file())
+        self.props = context.scene.BIMSystemProperties
+
+        row = self.layout.row(align=True)
+        row.label(text="{} Systems Found".format(len(Data.systems)), icon="OUTLINER")
+        if self.props.is_editing:
+            row.operator("bim.add_system", text="", icon="ADD")
+            row.operator("bim.disable_system_editing_ui", text="", icon="CANCEL")
+        else:
+            row.operator("bim.load_systems", text="", icon="GREASEPENCIL")
+
+        if self.props.is_editing:
+            self.layout.template_list(
+                "BIM_UL_systems",
+                "",
+                self.props,
+                "systems",
+                self.props,
+                "active_system_index",
+            )
+
+        if self.props.active_system_id:
+            self.draw_editable_ui(context)
+
+    def draw_editable_ui(self, context):
+        for attribute in self.props.system_attributes:
+            row = self.layout.row(align=True)
+            row.prop(attribute, "string_value", text=attribute.name)
+            if attribute.is_optional:
+                row.prop(attribute, "is_null", icon="RADIOBUT_OFF" if attribute.is_null else "RADIOBUT_ON", text="")
+
+
+
+class BIM_UL_systems(UIList):
+    def draw_item(self, context, layout, data, item, icon, active_data, active_propname):
+        if item:
+            row = layout.row(align=True)
+            row.label(text=item.name)
+
+            if context.active_object:
+                oprops = context.active_object.BIMObjectProperties
+                if (
+                    oprops.ifc_definition_id in Data.products
+                    and item.ifc_definition_id in Data.products[oprops.ifc_definition_id]
+                ):
+                    op = row.operator("bim.unassign_system", text="", icon="KEYFRAME_HLT", emboss=False)
+                    op.system = item.ifc_definition_id
+                else:
+                    op = row.operator("bim.assign_system", text="", icon="KEYFRAME", emboss=False)
+                    op.system = item.ifc_definition_id
+
+            if context.scene.BIMSystemProperties.active_system_id == item.ifc_definition_id:
+                op = row.operator("bim.select_system_products", text="", icon="RESTRICT_SELECT_OFF")
+                op.system = item.ifc_definition_id
+                row.operator("bim.edit_system", text="", icon="CHECKMARK")
+                row.operator("bim.disable_editing_system", text="", icon="CANCEL")
+            elif context.scene.BIMSystemProperties.active_system_id:
+                op = row.operator("bim.select_system_products", text="", icon="RESTRICT_SELECT_OFF")
+                op.system = item.ifc_definition_id
+                row.operator("bim.remove_system", text="", icon="X").system = item.ifc_definition_id
+            else:
+                op = row.operator("bim.select_system_products", text="", icon="RESTRICT_SELECT_OFF")
+                op.system = item.ifc_definition_id
+                op = row.operator("bim.enable_editing_system", text="", icon="GREASEPENCIL")
+                op.system = item.ifc_definition_id
+                row.operator("bim.remove_system", text="", icon="X").system = item.ifc_definition_id
diff --git a/src/ifcopenshell-python/ifcopenshell/api/system/add_system.py b/src/ifcopenshell-python/ifcopenshell/api/system/add_system.py
new file mode 100644
index 0000000000..b3226724c5
--- /dev/null
+++ b/src/ifcopenshell-python/ifcopenshell/api/system/add_system.py
@@ -0,0 +1,17 @@
+import ifcopenshell
+import ifcopenshell.api
+
+
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {}
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        return self.file.create_entity("IfcSystem", **{
+            "GlobalId": ifcopenshell.guid.new(),
+            "OwnerHistory": ifcopenshell.api.run("owner.create_owner_history", self.file),
+            "Name": "Unnamed"
+        })
diff --git a/src/ifcopenshell-python/ifcopenshell/api/system/assign_system.py b/src/ifcopenshell-python/ifcopenshell/api/system/assign_system.py
new file mode 100644
index 0000000000..265afac4bd
--- /dev/null
+++ b/src/ifcopenshell-python/ifcopenshell/api/system/assign_system.py
@@ -0,0 +1,27 @@
+import ifcopenshell
+import ifcopenshell.api
+
+
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {
+            "product": None,
+            "system": None,
+        }
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        if not self.settings["system"].IsGroupedBy:
+            return self.file.create_entity("IfcRelAssignsToGroup", **{
+                "GlobalId": ifcopenshell.guid.new(),
+                "OwnerHistory": ifcopenshell.api.run("owner.create_owner_history", self.file),
+                "RelatedObjects": [self.settings["product"]],
+                "RelatingGroup": self.settings["system"]
+            })
+        rel = self.settings["system"].IsGroupedBy[0]
+        related_objects = set(rel.RelatedObjects) or set()
+        related_objects.add(self.settings["product"])
+        rel.RelatedObjects = list(related_objects)
+        ifcopenshell.api.run("owner.update_owner_history", self.file, **{"element": rel})
diff --git a/src/ifcopenshell-python/ifcopenshell/api/system/data.py b/src/ifcopenshell-python/ifcopenshell/api/system/data.py
new file mode 100644
index 0000000000..2a171f6a50
--- /dev/null
+++ b/src/ifcopenshell-python/ifcopenshell/api/system/data.py
@@ -0,0 +1,24 @@
+class Data:
+    is_loaded = False
+    products = {}
+    systems = {}
+
+    @classmethod
+    def purge(cls):
+        cls.is_loaded = False
+        cls.products = {}
+        cls.systems = {}
+
+    @classmethod
+    def load(cls, file):
+        cls.products = {}
+        cls.systems = {}
+        for system in file.by_type("IfcSystem", include_subtypes=False):
+            if system.IsGroupedBy:
+                for rel in system.IsGroupedBy:
+                    for product in rel.RelatedObjects:
+                        cls.products.setdefault(product.id(), []).append(system.id())
+            data = system.get_info()
+            del data["OwnerHistory"]
+            cls.systems[system.id()] = data
+        cls.is_loaded=True
diff --git a/src/ifcopenshell-python/ifcopenshell/api/system/edit_system.py b/src/ifcopenshell-python/ifcopenshell/api/system/edit_system.py
new file mode 100644
index 0000000000..734e9937c3
--- /dev/null
+++ b/src/ifcopenshell-python/ifcopenshell/api/system/edit_system.py
@@ -0,0 +1,13 @@
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {
+            "system": None,
+            "attributes": {}
+        }
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        for name, value in self.settings["attributes"].items():
+            setattr(self.settings["system"], name, value)
diff --git a/src/ifcopenshell-python/ifcopenshell/api/system/remove_system.py b/src/ifcopenshell-python/ifcopenshell/api/system/remove_system.py
new file mode 100644
index 0000000000..9cc1a6ec93
--- /dev/null
+++ b/src/ifcopenshell-python/ifcopenshell/api/system/remove_system.py
@@ -0,0 +1,11 @@
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {"system": None}
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        for rel in self.settings["system"].IsGroupedBy or []:
+            self.file.remove(rel)
+        self.file.remove(self.settings["system"])
diff --git a/src/ifcopenshell-python/ifcopenshell/api/system/unassign_system.py b/src/ifcopenshell-python/ifcopenshell/api/system/unassign_system.py
new file mode 100644
index 0000000000..d072f74623
--- /dev/null
+++ b/src/ifcopenshell-python/ifcopenshell/api/system/unassign_system.py
@@ -0,0 +1,25 @@
+import ifcopenshell
+import ifcopenshell.api
+
+
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {
+            "product": None,
+            "system": None,
+        }
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        if not self.settings["system"].IsGroupedBy:
+            return
+        rel = self.settings["system"].IsGroupedBy[0]
+        related_objects = set(rel.RelatedObjects) or set()
+        related_objects.remove(self.settings["product"])
+        if len(related_objects):
+            rel.RelatedObjects = list(related_objects)
+            ifcopenshell.api.run("owner.update_owner_history", self.file, **{"element": rel})
+        else:
+            self.file.remove(rel)
diff --git a/src/ifcopenshell-python/ifcopenshell/api/type/data.py b/src/ifcopenshell-python/ifcopenshell/api/type/data.py
index ac8cd509aa..c768bd6cf2 100644
--- a/src/ifcopenshell-python/ifcopenshell/api/type/data.py
+++ b/src/ifcopenshell-python/ifcopenshell/api/type/data.py
@@ -1,18 +1,40 @@
 class Data:
     products = {}
+    types = {}
 
     @classmethod
     def purge(cls):
         cls.products = {}
+        cls.types = {}
 
     @classmethod
     def load(cls, file, product_id):
         if not file:
             return
+        cls.file = file
         product = file.by_id(product_id)
-        if file.schema == "IFC2X3" and not hasattr(product, "IsDefinedBy"):
+        if product.is_a("IfcTypeObject"):
+            cls.load_type(product_id)
+        else:
+            cls.load_product(product_id)
+
+    @classmethod
+    def load_type(cls, product_id):
+        product = cls.file.by_id(product_id)
+        cls.types[product_id] = None
+        if cls.file.schema == "IFC2X3":
+            if hasattr(product, "ObjectTypeOf"):
+                cls.types[product_id] = [o.id() for o in product.ObjectTypeOf[0].RelatedObjects]
+        else:
+            if hasattr(product, "Types"):
+                cls.types[product_id] = [o.id() for o in product.Types[0].RelatedObjects]
+
+    @classmethod
+    def load_product(cls, product_id):
+        product = cls.file.by_id(product_id)
+        if cls.file.schema == "IFC2X3" and not hasattr(product, "IsDefinedBy"):
             cls.products[product_id] = None
-        elif file.schema != "IFC2X3" and not hasattr(product, "IsTypedBy"):
+        elif cls.file.schema != "IFC2X3" and not hasattr(product, "IsTypedBy"):
             cls.products[product_id] = None
         elif hasattr(product, "IsTypedBy") and product.IsTypedBy:
             type = product.IsTypedBy[0].RelatingType