diff --git a/blueprintcompiler/gir.py b/blueprintcompiler/gir.py
index 6dab652..3642bd6 100644
--- a/blueprintcompiler/gir.py
+++ b/blueprintcompiler/gir.py
@@ -136,6 +136,14 @@ class GirType:
     def incomplete(self) -> bool:
         return False
 
+    @property
+    def deprecated(self) -> bool:
+        return False
+
+    @property
+    def deprecated_doc(self) -> T.Optional[str]:
+        return None
+
 
 class ExternType(GirType):
     def __init__(self, name: str) -> None:
@@ -330,6 +338,13 @@ class GirNode:
     def type(self) -> GirType:
         raise NotImplementedError()
 
+    @property
+    def deprecated_doc(self) -> T.Optional[str]:
+        try:
+            return self.xml.get_elements("doc-deprecated")[0].cdata.strip()
+        except:
+            return None
+
 
 class Property(GirNode):
     xml_tag = "property"
@@ -365,6 +380,10 @@ class Property(GirNode):
         else:
             return None
 
+    @property
+    def deprecated(self) -> bool:
+        return self.tl.PROP_DEPRECATED == 1
+
 
 class Argument(GirNode):
     def __init__(self, container: GirNode, tl: typelib.Typelib) -> None:
@@ -427,6 +446,10 @@ class Signal(GirNode):
         else:
             return None
 
+    @property
+    def deprecated(self) -> bool:
+        return self.tl.SIGNAL_DEPRECATED == 1
+
 
 class Interface(GirNode, GirType):
     xml_tag = "interface"
@@ -488,6 +511,10 @@ class Interface(GirNode, GirType):
         else:
             return None
 
+    @property
+    def deprecated(self) -> bool:
+        return self.tl.INTERFACE_DEPRECATED == 1
+
 
 class Class(GirNode, GirType):
     xml_tag = "class"
@@ -609,6 +636,10 @@ class Class(GirNode, GirType):
         else:
             return None
 
+    @property
+    def deprecated(self) -> bool:
+        return self.tl.OBJ_DEPRECATED == 1
+
 
 class TemplateType(GirType):
     def __init__(self, name: str, parent: T.Optional[GirType]):
@@ -722,6 +753,10 @@ class Enumeration(GirNode, GirType):
         else:
             return None
 
+    @property
+    def deprecated(self) -> bool:
+        return self.tl.ENUM_DEPRECATED == 1
+
 
 class Boxed(GirNode, GirType):
     xml_tag = "glib:boxed"
@@ -743,6 +778,10 @@ class Boxed(GirNode, GirType):
         else:
             return None
 
+    @property
+    def deprecated(self) -> bool:
+        return self.tl.STRUCT_DEPRECATED == 1
+
 
 class Bitfield(Enumeration):
     xml_tag = "bitfield"
diff --git a/blueprintcompiler/language/gobject_property.py b/blueprintcompiler/language/gobject_property.py
index b24cd07..526b308 100644
--- a/blueprintcompiler/language/gobject_property.py
+++ b/blueprintcompiler/language/gobject_property.py
@@ -41,9 +41,11 @@ class Property(AstNode):
         return self.parent.parent.gir_class
 
     @property
-    def gir_property(self):
+    def gir_property(self) -> T.Optional[gir.Property]:
         if self.gir_class is not None and not isinstance(self.gir_class, ExternType):
             return self.gir_class.properties.get(self.tokens["name"])
+        else:
+            return None
 
     @validate()
     def binding_valid(self):
@@ -91,6 +93,17 @@ class Property(AstNode):
             check=lambda child: child.tokens["name"] == self.tokens["name"],
         )
 
+    @validate("name")
+    def deprecated(self) -> None:
+        if self.gir_property is not None and self.gir_property.deprecated:
+            hints = []
+            if self.gir_property.deprecated_doc:
+                hints.append(self.gir_property.deprecated_doc)
+            raise CompileWarning(
+                f"{self.gir_property.signature} is deprecated",
+                hints=hints,
+            )
+
     @docs("name")
     def property_docs(self):
         if self.gir_property is not None:
diff --git a/blueprintcompiler/language/gobject_signal.py b/blueprintcompiler/language/gobject_signal.py
index 2fc4699..1c60bbf 100644
--- a/blueprintcompiler/language/gobject_signal.py
+++ b/blueprintcompiler/language/gobject_signal.py
@@ -95,9 +95,11 @@ class Signal(AstNode):
         return any(x.flag == "after" for x in self.flags)
 
     @property
-    def gir_signal(self):
+    def gir_signal(self) -> T.Optional[gir.Signal]:
         if self.gir_class is not None and not isinstance(self.gir_class, ExternType):
             return self.gir_class.signals.get(self.tokens["name"])
+        else:
+            return None
 
     @property
     def gir_class(self):
@@ -134,6 +136,17 @@ class Signal(AstNode):
         if self.context[ScopeCtx].objects.get(object_id) is None:
             raise CompileError(f"Could not find object with ID '{object_id}'")
 
+    @validate("name")
+    def deprecated(self) -> None:
+        if self.gir_signal is not None and self.gir_signal.deprecated:
+            hints = []
+            if self.gir_signal.deprecated_doc:
+                hints.append(self.gir_signal.deprecated_doc)
+            raise CompileWarning(
+                f"{self.gir_signal.signature} is deprecated",
+                hints=hints,
+            )
+
     @docs("name")
     def signal_docs(self):
         if self.gir_signal is not None:
diff --git a/blueprintcompiler/language/types.py b/blueprintcompiler/language/types.py
index e75ebdc..1d9911b 100644
--- a/blueprintcompiler/language/types.py
+++ b/blueprintcompiler/language/types.py
@@ -57,6 +57,17 @@ class TypeName(AstNode):
         if not self.tokens["extern"]:
             self.root.gir.validate_ns(self.tokens["namespace"])
 
+    @validate()
+    def deprecated(self) -> None:
+        if self.gir_type and self.gir_type.deprecated:
+            hints = []
+            if self.gir_type.deprecated_doc:
+                hints.append(self.gir_type.deprecated_doc)
+            raise CompileWarning(
+                f"{self.gir_type.full_name} is deprecated",
+                hints=hints,
+            )
+
     @property
     def gir_ns(self):
         if not self.tokens["extern"]:
diff --git a/blueprintcompiler/typelib.py b/blueprintcompiler/typelib.py
index 2ce3e32..c8a3ff3 100644
--- a/blueprintcompiler/typelib.py
+++ b/blueprintcompiler/typelib.py
@@ -150,11 +150,15 @@ class Typelib:
 
     BLOB_NAME = Field(0x4, "string")
 
+    STRUCT_DEPRECATED = Field(0x2, "u16", 0, 1)
+
+    ENUM_DEPRECATED = Field(0x2, "u16", 0, 1)
     ENUM_GTYPE_NAME = Field(0x8, "string")
     ENUM_N_VALUES = Field(0x10, "u16")
     ENUM_N_METHODS = Field(0x12, "u16")
     ENUM_VALUES = Field(0x18, "offset")
 
+    INTERFACE_DEPRECATED = Field(0x2, "u16", 0, 1)
     INTERFACE_GTYPE_NAME = Field(0x8, "string")
     INTERFACE_N_PREREQUISITES = Field(0x12, "u16")
     INTERFACE_N_PROPERTIES = Field(0x14, "u16")
diff --git a/tests/sample_errors/deprecations.blp b/tests/sample_errors/deprecations.blp
new file mode 100644
index 0000000..1554a0b
--- /dev/null
+++ b/tests/sample_errors/deprecations.blp
@@ -0,0 +1,10 @@
+using Gtk 4.0;
+using Gio 2.0;
+
+Dialog {
+  use-header-bar: 1;
+}
+
+Window {
+  keys-changed => $on_window_keys_changed();
+}
diff --git a/tests/sample_errors/deprecations.err b/tests/sample_errors/deprecations.err
new file mode 100644
index 0000000..6059412
--- /dev/null
+++ b/tests/sample_errors/deprecations.err
@@ -0,0 +1 @@
+4,1,6,Gtk.Dialog is deprecated
\ No newline at end of file
diff --git a/tests/sample_errors/legacy_template.err b/tests/sample_errors/legacy_template.err
index 876b0cf..79ad519 100644
--- a/tests/sample_errors/legacy_template.err
+++ b/tests/sample_errors/legacy_template.err
@@ -1,2 +1,3 @@
 3,10,12,Use type syntax here (introduced in blueprint 0.8.0)
+8,1,6,Gtk.Dialog is deprecated
 9,18,12,Use 'template' instead of the class name (introduced in 0.8.0)
\ No newline at end of file
diff --git a/tests/test_samples.py b/tests/test_samples.py
index 7fe7941..1273805 100644
--- a/tests/test_samples.py
+++ b/tests/test_samples.py
@@ -54,6 +54,14 @@ class TestSamples(unittest.TestCase):
             tokens = tokenizer.tokenize(blueprint)
             ast, errors, warnings = parser.parse(tokens)
 
+            # Ignore deprecation warnings because some of the things we're testing
+            # are deprecated
+            warnings = [
+                warning
+                for warning in warnings
+                if "is deprecated" not in warning.message
+            ]
+
             if errors:
                 raise errors
             if len(warnings):