diff --git a/web_poet/__init__.py b/web_poet/__init__.py
index 3c8b0112..c0212889 100644
--- a/web_poet/__init__.py
+++ b/web_poet/__init__.py
@@ -1,4 +1,4 @@
-from .fields import field, item_from_fields, item_from_fields_sync
+from .fields import Unset, UnsetType, field, item_from_fields, item_from_fields_sync
 from .page_inputs import (
     BrowserHtml,
     HttpClient,
diff --git a/web_poet/fields.py b/web_poet/fields.py
index d85fd93d..92acbd84 100644
--- a/web_poet/fields.py
+++ b/web_poet/fields.py
@@ -178,3 +178,20 @@ def _without_unsupported_field_names(
     if item_field_names is None:  # item_cls doesn't define field names upfront
         return field_names[:]
     return list(set(field_names) & set(item_field_names))
+
+
+# TODO: enforce singleton
+class UnsetType:
+    def __repr__(self) -> str:
+        return "Unset"
+
+    def __str__(self) -> str:
+        return self.__repr__()
+
+    def __bool__(self) -> bool:
+        return False
+
+
+# Represents a field that hasn't been set with any values instead of being
+# None.
+Unset = UnsetType()