diff --git a/inject/__init__.py b/inject/__init__.py
index 100784f..a952186 100644
--- a/inject/__init__.py
+++ b/inject/__init__.py
@@ -104,6 +104,14 @@ def my_config(binder):
 _INJECTOR_LOCK = threading.RLock()  # Guards injector initialization.
 _BINDING_LOCK = threading.RLock()  # Guards runtime bindings.
 
+MARKER = object()  # A marker object to explicitly set a parameter to be injected
+
+
+def set_marker(new_marker: Any):
+    global MARKER
+    MARKER = new_marker
+
+
 Injectable = Union[object, Any]
 T = TypeVar('T', bound=Injectable)
 Binding = Union[Type[Injectable], Hashable]
@@ -328,11 +336,17 @@ def __call__(self, func: Callable[..., Union[Awaitable[T], T]]) -> Callable[...,
         if inspect.iscoroutinefunction(func):
             @wraps(func)
             async def async_injection_wrapper(*args: Any, **kwargs: Any) -> T:
-                provided_params = frozenset(
-                    arg_names[:len(args)]) | frozenset(kwargs.keys())
+                arg_name_tuple = arg_names[:len(args)]
+                provided_params = frozenset(arg_name_tuple) | frozenset(kwargs.keys())
                 for param, cls in params_to_provide.items():
                     if param not in provided_params:
                         kwargs[param] = instance(cls)
+                    elif param in kwargs and kwargs[param] is MARKER:
+                        kwargs[param] = instance(cls)
+                    elif param in arg_name_tuple:
+                        idx = arg_name_tuple.index(param)
+                        if args[idx] is MARKER:
+                            args = args[:idx] + (instance(cls),) + args[idx + 1:]
                 async_func = cast(Callable[..., Awaitable[T]], func)
                 try:
                     return await async_func(*args, **kwargs)
@@ -343,11 +357,17 @@ async def async_injection_wrapper(*args: Any, **kwargs: Any) -> T:
 
         @wraps(func)
         def injection_wrapper(*args: Any, **kwargs: Any) -> T:
-            provided_params = frozenset(
-                arg_names[:len(args)]) | frozenset(kwargs.keys())
+            arg_name_tuple = arg_names[:len(args)]
+            provided_params = frozenset(arg_name_tuple) | frozenset(kwargs.keys())
             for param, cls in params_to_provide.items():
                 if param not in provided_params:
                     kwargs[param] = instance(cls)
+                elif param in kwargs and kwargs[param] is MARKER:
+                    kwargs[param] = instance(cls)
+                elif param in arg_name_tuple:
+                    idx = arg_name_tuple.index(param)
+                    if args[idx] is MARKER:
+                        args = args[:idx] + (instance(cls),) + args[idx + 1:]
             sync_func = cast(Callable[..., T], func)
             try:
                 return sync_func(*args, **kwargs)
diff --git a/test/test_autoparams.py b/test/test_autoparams.py
index dda87f4..9ea7a61 100644
--- a/test/test_autoparams.py
+++ b/test/test_autoparams.py
@@ -17,6 +17,8 @@ def test_func(val: int = None):
         inject.configure(lambda binder: binder.bind(int, 123))
 
         assert test_func() == 123
+        assert test_func(inject.MARKER) == 123
+        assert test_func(val=inject.MARKER) == 123
         assert test_func(val=321) == 321
 
     def test_autoparams_multi(self):
@@ -33,8 +35,11 @@ def config(binder):
 
         assert test_func() == (1, 2, 3)
         assert test_func(10) == (10, 2, 3)
+        assert test_func(10, inject.MARKER) == (10, 2, 3)
+        assert test_func(10, 20) == (10, 20, 3)
         assert test_func(10, 20) == (10, 20, 3)
         assert test_func(10, 20, c=30) == (10, 20, 30)
+        assert test_func(a=inject.MARKER) == (1, 2, 3)
         assert test_func(a='a') == ('a', 2, 3)
         assert test_func(b='b') == (1, 'b', 3)
         assert test_func(c='c') == (1, 2, 'c')
@@ -56,8 +61,10 @@ def config(binder):
 
         assert test_func() == (1, 2, 3)
         assert test_func(10) == (10, 2, 3)
+        assert test_func(10, inject.MARKER) == (10, 2, 3)
         assert test_func(10, 20) == (10, 20, 3)
         assert test_func(10, 20, c=30) == (10, 20, 30)
+        assert test_func(a=inject.MARKER) == (1, 2, 3)
         assert test_func(a='a') == ('a', 2, 3)
         assert test_func(b='b') == (1, 'b', 3)
         assert test_func(c='c') == (1, 2, 'c')
@@ -78,9 +85,11 @@ def config(binder):
 
         assert test_func() == (1, 2, 3)
         assert test_func(10) == (10, 2, 3)
+        assert test_func(10, inject.MARKER) == (10, 2, 3)
         assert test_func(10, 20) == (10, 20, 3)
         assert test_func(10, 20, c=30) == (10, 20, 30)
         assert test_func(a='a') == ('a', 2, 3)
+        assert test_func(b=inject.MARKER) == (1, 2, 3)
         assert test_func(b='b') == (1, 'b', 3)
         assert test_func(c='c') == (1, 2, 'c')
         assert test_func(a=10, c=30) == (10, 2, 30)
@@ -102,9 +111,11 @@ def config(binder):
 
         assert test.func() == (test, 1, 2, 3)
         assert test.func(10) == (test, 10, 2, 3)
+        assert test.func(10, inject.MARKER) == (test, 10, 2, 3)
         assert test.func(10, 20) == (test, 10, 20, 3)
         assert test.func(10, 20, c=30) == (test, 10, 20, 30)
         assert test.func(a='a') == (test, 'a', 2, 3)
+        assert test.func(b=inject.MARKER) == (test, 1, 2, 3)
         assert test.func(b='b') == (test, 1, 'b', 3)
         assert test.func(c='c') == (test, 1, 2, 'c')
         assert test.func(a=10, c=30) == (test, 10, 2, 30)
@@ -127,9 +138,11 @@ def config(binder):
 
         assert Test.func() == (Test, 1, 2, 3)
         assert Test.func(10) == (Test, 10, 2, 3)
+        assert Test.func(10, inject.MARKER) == (Test, 10, 2, 3)
         assert Test.func(10, 20) == (Test, 10, 20, 3)
         assert Test.func(10, 20, c=30) == (Test, 10, 20, 30)
         assert Test.func(a='a') == (Test, 'a', 2, 3)
+        assert Test.func(b=inject.MARKER) == (Test, 1, 2, 3)
         assert Test.func(b='b') == (Test, 1, 'b', 3)
         assert Test.func(c='c') == (Test, 1, 2, 'c')
         assert Test.func(a=10, c=30) == (Test, 10, 2, 30)
@@ -153,9 +166,11 @@ def config(binder):
 
         assert test.func() == (Test, 1, 2, 3)
         assert test.func(10) == (Test, 10, 2, 3)
+        assert test.func(10, inject.MARKER) == (Test, 10, 2, 3)
         assert test.func(10, 20) == (Test, 10, 20, 3)
         assert test.func(10, 20, c=30) == (Test, 10, 20, 30)
         assert test.func(a='a') == (Test, 'a', 2, 3)
+        assert test.func(b=inject.MARKER) == (Test, 1, 2, 3)
         assert test.func(b='b') == (Test, 1, 'b', 3)
         assert test.func(c='c') == (Test, 1, 2, 'c')
         assert test.func(a=10, c=30) == (Test, 10, 2, 30)
diff --git a/test/test_params.py b/test/test_params.py
index fc2e8dc..d079ea5 100644
--- a/test/test_params.py
+++ b/test/test_params.py
@@ -12,7 +12,9 @@ def test_func(val):
         inject.configure(lambda binder: binder.bind(int, 123))
 
         assert test_func() == 123
+        assert test_func(inject.MARKER) == 123
         assert test_func(321) == 321
+        assert test_func(val=inject.MARKER) == 123
         assert test_func(val=42) == 42
 
     def test_params_multi(self):
@@ -29,8 +31,10 @@ def config(binder):
 
         assert test_func() == (1, 2, 3)
         assert test_func(10) == (10, 2, 3)
+        assert test_func(10, inject.MARKER) == (10, 2, 3)
         assert test_func(10, 20) == (10, 20, 3)
         assert test_func(10, 20, 30) == (10, 20, 30)
+        assert test_func(a=inject.MARKER) == (1, 2, 3)
         assert test_func(a='a') == ('a', 2, 3)
         assert test_func(b='b') == (1, 'b', 3)
         assert test_func(c='c') == (1, 2, 'c')
@@ -52,12 +56,14 @@ def config(binder):
 
         assert test_func() == (1, 2, 3)
         assert test_func(10) == (10, 2, 3)
+        assert test_func(10, inject.MARKER) == (10, 2, 3)
         assert test_func(10, 20) == (10, 20, 3)
         assert test_func(10, 20, 30) == (10, 20, 30)
         assert test_func(a='a') == ('a', 2, 3)
         assert test_func(b='b') == (1, 'b', 3)
         assert test_func(c='c') == (1, 2, 'c')
         assert test_func(a=10, c=30) == (10, 2, 30)
+        assert test_func(a=10, b=inject.MARKER, c=30) == (10, 2, 30)
         assert test_func(c=30, b=20, a=10) == (10, 20, 30)
         assert test_func(10, b=20) == (10, 20, 3)
 
@@ -78,10 +84,12 @@ def config(binder):
         assert test.func(10) == (test, 10, 2, 3)
         assert test.func(10, 20) == (test, 10, 20, 3)
         assert test.func(10, 20, 30) == (test, 10, 20, 30)
+        assert test.func(10, inject.MARKER, inject.MARKER) == (test, 10, 2, 3)
         assert test.func(a='a') == (test, 'a', 2, 3)
         assert test.func(b='b') == (test, 1, 'b', 3)
         assert test.func(c='c') == (test, 1, 2, 'c')
         assert test.func(a=10, c=30) == (test, 10, 2, 30)
+        assert test.func(a=10, b=inject.MARKER, c=30) == (test, 10, 2, 30)
         assert test.func(c=30, b=20, a=10) == (test, 10, 20, 30)
         assert test.func(10, b=20) == (test, 10, 20, 3)
 
@@ -103,10 +111,12 @@ def config(binder):
         assert Test.func(10) == (Test, 10, 2, 3)
         assert Test.func(10, 20) == (Test, 10, 20, 3)
         assert Test.func(10, 20, 30) == (Test, 10, 20, 30)
+        assert Test.func(10, inject.MARKER, inject.MARKER) == (Test, 10, 2, 3)
         assert Test.func(a='a') == (Test, 'a', 2, 3)
         assert Test.func(b='b') == (Test, 1, 'b', 3)
         assert Test.func(c='c') == (Test, 1, 2, 'c')
         assert Test.func(a=10, c=30) == (Test, 10, 2, 30)
+        assert Test.func(a=10, b=inject.MARKER, c=30) == (Test, 10, 2, 30)
         assert Test.func(c=30, b=20, a=10) == (Test, 10, 20, 30)
         assert Test.func(10, b=20) == (Test, 10, 20, 3)
 
@@ -129,10 +139,12 @@ def config(binder):
         assert test.func(10) == (Test, 10, 2, 3)
         assert test.func(10, 20) == (Test, 10, 20, 3)
         assert test.func(10, 20, 30) == (Test, 10, 20, 30)
+        assert test.func(10, inject.MARKER, inject.MARKER) == (Test, 10, 2, 3)
         assert test.func(a='a') == (Test, 'a', 2, 3)
         assert test.func(b='b') == (Test, 1, 'b', 3)
         assert test.func(c='c') == (Test, 1, 2, 'c')
         assert test.func(a=10, c=30) == (Test, 10, 2, 30)
+        assert test.func(a=10, b=inject.MARKER, c=30) == (Test, 10, 2, 30)
         assert test.func(c=30, b=20, a=10) == (Test, 10, 20, 30)
         assert test.func(10, b=20) == (Test, 10, 20, 3)
 
@@ -145,5 +157,7 @@ async def test_func(val):
 
         assert inspect.iscoroutinefunction(test_func)
         assert self.run_async(test_func()) == 123
+        assert self.run_async(test_func(inject.MARKER)) == 123
         assert self.run_async(test_func(321)) == 321
+        assert self.run_async(test_func(val=inject.MARKER)) == 123
         assert self.run_async(test_func(val=42)) == 42