diff --git a/baseclasses/__init__.py b/baseclasses/__init__.py
index 5b23643..41f6d29 100644
--- a/baseclasses/__init__.py
+++ b/baseclasses/__init__.py
@@ -1,4 +1,4 @@
-__version__ = "1.8.5"
+__version__ = "1.9.0"
 
 from .problems import (
     AeroProblem,
diff --git a/baseclasses/testing/__init__.py b/baseclasses/testing/__init__.py
index 69ebece..638a9cb 100644
--- a/baseclasses/testing/__init__.py
+++ b/baseclasses/testing/__init__.py
@@ -1,4 +1,4 @@
 from .pyRegTest import BaseRegTest, getTol
-from .decorators import require_mpi
+from .decorators import require_mpi, expire_deprecation
 
-__all__ = ["BaseRegTest", "getTol", "require_mpi"]
+__all__ = ["BaseRegTest", "getTol", "require_mpi", "expire_deprecation"]
diff --git a/baseclasses/testing/decorators.py b/baseclasses/testing/decorators.py
index ab15825..0138598 100644
--- a/baseclasses/testing/decorators.py
+++ b/baseclasses/testing/decorators.py
@@ -1,4 +1,8 @@
 import functools
+from importlib.metadata import version
+from typing import Optional
+import warnings
+from packaging.version import Version
 import unittest
 from importlib.util import find_spec
 
@@ -62,3 +66,44 @@ def skip_wrapper(*args, **kwargs):
     # module found, we just return the function and proceed normally
     else:
         return func
+
+
+def expire_deprecation(package_name: str, removal_version: str, new_name: Optional[str] = None):
+    """Decorator for methods that have been deprecated and potentially replaced by a new method
+
+    This decorator will raise a warning when the decorated method is called, and will raise an error if the current
+    version of the package is greater than or equal to the specified removal version, helping to ensure that deprecated
+    APIs are removed in a timely manner.
+
+    Parameters
+    ----------
+    package_name : str
+        _description_
+    removal_version : str
+        _description_
+    new_name : Optional[str], optional
+        _description_, by default None
+    """
+    removal = Version(removal_version)
+    current = Version(version(package_name))
+
+    def decorator(func):
+        if current >= removal:
+            raise AssertionError(
+                f"{func.__qualname__}: deprecated API should have been "
+                f"removed in {package_name} v{removal} "
+                f"(current: v{current}). Please delete this shim."
+            )
+
+        msg = f"{func.__name__}() is deprecated and will be removed in {package_name} v{removal}."
+        if new_name is not None:
+            msg += f" Use {new_name} instead."
+
+        @functools.wraps(func)
+        def wrapper(self, *args, **kwargs):
+            warnings.warn(msg, DeprecationWarning, stacklevel=2)
+            return func(self, *args, **kwargs)
+
+        return wrapper
+
+    return decorator
diff --git a/setup.py b/setup.py
index ed103ff..0f86b96 100644
--- a/setup.py
+++ b/setup.py
@@ -29,6 +29,7 @@
     python_requires=">=3.11",
     install_requires=[
         "numpy>=1.25",
+        "packaging",
     ],
     extras_require={
         "docs": docs_require,