diff --git a/lib/net/imap/config/attr_inheritance.rb b/lib/net/imap/config/attr_inheritance.rb
index d5618fba..c62539a6 100644
--- a/lib/net/imap/config/attr_inheritance.rb
+++ b/lib/net/imap/config/attr_inheritance.rb
@@ -66,11 +66,31 @@ def new(**attrs) self.class.new(self, **attrs) end
         # inherited, or +false+ if any of them are overriden.  When no +attrs+
         # are given, returns +true+ if *all* attributes are inherited, or
         # +false+ if any attribute is overriden.
+        #
+        # Related: #overrides?
         def inherited?(*attrs)
           attrs = data.members if attrs.empty?
           attrs.all? { data[_1] == INHERITED }
         end
 
+        # :call-seq:
+        #   overrides?(attr)   -> true or false
+        #   overrides?(*attrs) -> true or false
+        #   overrides?         -> true or false
+        #
+        # Returns +true+ if +attr+ is defined on this config and not inherited
+        # from #parent.
+        #
+        # When multiple +attrs+ are given, returns +true+ if
+        # *any* of them are defined on +self+.  When no +attrs+ are given,
+        # returns +true+ if *any* attribute is overriden.
+        #
+        # Related: #inherited?
+        def overrides?(*attrs)
+          attrs = data.members if attrs.empty?
+          attrs.any? { data[_1] != INHERITED }
+        end
+
         # :call-seq:
         #   reset -> self
         #   reset(attr) -> attribute value
diff --git a/test/net/imap/test_config.rb b/test/net/imap/test_config.rb
index 8e1ac569..13671bc7 100644
--- a/test/net/imap/test_config.rb
+++ b/test/net/imap/test_config.rb
@@ -349,6 +349,33 @@ def duck.to_r   = 1/11111
     assert child.inherited?(:debug, :idle_response_timeout, :open_timeout)
   end
 
+  test "#overrides?" do
+    base = Config.new debug: false, open_timeout: 99, idle_response_timeout: 15
+    child = base.new debug: true, open_timeout: 15, idle_response_timeout: 10
+    assert child.overrides?
+    assert child.overrides?(:idle_response_timeout)
+    assert child.overrides?(:idle_response_timeout, :open_timeout)
+    assert child.overrides?(:sasl_ir, :open_timeout)
+    refute child.overrides?(:sasl_ir, :max_response_size)
+    refute child.overrides?(:sasl_ir)
+
+    child.reset(:idle_response_timeout)
+    assert child.overrides?
+    refute child.overrides?(:idle_response_timeout)
+    assert child.overrides?(:idle_response_timeout, :open_timeout)
+    assert child.overrides?(:sasl_ir, :open_timeout)
+    refute child.overrides?(:sasl_ir, :max_response_size)
+    refute child.overrides?(:sasl_ir)
+
+    child.reset
+    refute child.overrides?
+    refute child.overrides?(:idle_response_timeout)
+    refute child.overrides?(:idle_response_timeout, :open_timeout)
+    refute child.overrides?(:sasl_ir, :open_timeout)
+    refute child.overrides?(:sasl_ir, :max_response_size)
+    refute child.overrides?(:sasl_ir)
+  end
+
   test "#reset all attributes" do
     base = Config.new debug: false, open_timeout: 99, idle_response_timeout: 15
     child = base.new debug: true, open_timeout: 15, idle_response_timeout: 10