diff --git a/include/pybind11/detail/common.h b/include/pybind11/detail/common.h
index aea1987bf5..39531114cb 100644
--- a/include/pybind11/detail/common.h
+++ b/include/pybind11/detail/common.h
@@ -25,8 +25,10 @@
 // on the main `pybind11` namespace.
 #if !defined(PYBIND11_NAMESPACE)
 #    ifdef __GNUG__
-#        define PYBIND11_NAMESPACE pybind11 __attribute__((visibility("hidden")))
+#        define PYBIND11_NS_VISIBILITY(...) __VA_ARGS__ __attribute__((visibility("hidden")))
+#        define PYBIND11_NAMESPACE PYBIND11_NS_VISIBILITY(pybind11)
 #    else
+#        define PYBIND11_NS_VISIBILITY(...) __VA_ARGS__
 #        define PYBIND11_NAMESPACE pybind11
 #    endif
 #endif
diff --git a/pybind11/setup_helpers.py b/pybind11/setup_helpers.py
index 1fd04b9154..1172406b4b 100644
--- a/pybind11/setup_helpers.py
+++ b/pybind11/setup_helpers.py
@@ -149,7 +149,6 @@ def __init__(self, *args: Any, **kwargs: Any) -> None:
         if WIN:
             cflags += ["/EHsc", "/bigobj"]
         else:
-            cflags += ["-fvisibility=hidden"]
             env_cflags = os.environ.get("CFLAGS", "")
             env_cppflags = os.environ.get("CPPFLAGS", "")
             c_cpp_flags = shlex.split(env_cflags) + shlex.split(env_cppflags)
diff --git a/tests/pybind11_cross_module_tests.cpp b/tests/pybind11_cross_module_tests.cpp
index 9379f3f259..92182a646a 100644
--- a/tests/pybind11_cross_module_tests.cpp
+++ b/tests/pybind11_cross_module_tests.cpp
@@ -48,7 +48,7 @@ PYBIND11_MODULE(pybind11_cross_module_tests, m) {
             if (p) {
                 std::rethrow_exception(p);
             }
-        } catch (const shared_exception &e) {
+        } catch (const pybind11_tests::shared_exception &e) {
             PyErr_SetString(PyExc_KeyError, e.what());
         }
     });
diff --git a/tests/test_class_sh_trampoline_basic.cpp b/tests/test_class_sh_trampoline_basic.cpp
index e31bcf7198..4cda66090b 100644
--- a/tests/test_class_sh_trampoline_basic.cpp
+++ b/tests/test_class_sh_trampoline_basic.cpp
@@ -4,7 +4,7 @@
 
 #include <memory>
 
-namespace pybind11_tests {
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NS_VISIBILITY(pybind11_tests))
 namespace class_sh_trampoline_basic {
 
 template <int SerNo> // Using int as a trick to easily generate a series of types.
@@ -74,7 +74,7 @@ void wrap(py::module_ m, const char *py_class_name) {
 }
 
 } // namespace class_sh_trampoline_basic
-} // namespace pybind11_tests
+PYBIND11_NAMESPACE_END(pybind11_tests)
 
 PYBIND11_SMART_HOLDER_TYPE_CASTERS(pybind11_tests::class_sh_trampoline_basic::Abase<0>)
 PYBIND11_SMART_HOLDER_TYPE_CASTERS(pybind11_tests::class_sh_trampoline_basic::Abase<1>)
diff --git a/tests/test_class_sh_trampoline_self_life_support.cpp b/tests/test_class_sh_trampoline_self_life_support.cpp
index c1eb035435..7630dcbfec 100644
--- a/tests/test_class_sh_trampoline_self_life_support.cpp
+++ b/tests/test_class_sh_trampoline_self_life_support.cpp
@@ -10,6 +10,7 @@
 #include <string>
 #include <utility>
 
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NS_VISIBILITY(pybind11_tests))
 namespace {
 
 struct Big5 { // Also known as "rule of five".
@@ -42,10 +43,13 @@ struct Big5Trampoline : Big5, py::trampoline_self_life_support {
 };
 
 } // namespace
+PYBIND11_NAMESPACE_END(pybind11_tests)
 
-PYBIND11_SMART_HOLDER_TYPE_CASTERS(Big5)
+PYBIND11_SMART_HOLDER_TYPE_CASTERS(pybind11_tests::Big5)
 
 TEST_SUBMODULE(class_sh_trampoline_self_life_support, m) {
+    using namespace pybind11_tests;
+
     py::classh<Big5, Big5Trampoline>(m, "Big5")
         .def(py::init<std::string>())
         .def_readonly("history", &Big5::history);
diff --git a/tests/test_class_sh_trampoline_shared_from_this.cpp b/tests/test_class_sh_trampoline_shared_from_this.cpp
index ae9f274659..fc3fb98cc9 100644
--- a/tests/test_class_sh_trampoline_shared_from_this.cpp
+++ b/tests/test_class_sh_trampoline_shared_from_this.cpp
@@ -8,6 +8,7 @@
 #include <memory>
 #include <string>
 
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NS_VISIBILITY(pybind11_tests))
 namespace {
 
 struct Sft : std::enable_shared_from_this<Sft> {
@@ -99,11 +100,14 @@ std::shared_ptr<Sft> make_pure_cpp_sft_shd_ptr(const std::string &history_seed)
 std::shared_ptr<Sft> pass_through_shd_ptr(const std::shared_ptr<Sft> &obj) { return obj; }
 
 } // namespace
+PYBIND11_NAMESPACE_END(pybind11_tests)
 
-PYBIND11_SMART_HOLDER_TYPE_CASTERS(Sft)
-PYBIND11_SMART_HOLDER_TYPE_CASTERS(SftSharedPtrStash)
+PYBIND11_SMART_HOLDER_TYPE_CASTERS(pybind11_tests::Sft)
+PYBIND11_SMART_HOLDER_TYPE_CASTERS(pybind11_tests::SftSharedPtrStash)
 
 TEST_SUBMODULE(class_sh_trampoline_shared_from_this, m) {
+    using namespace pybind11_tests;
+
     py::classh<Sft, SftTrampoline>(m, "Sft")
         .def(py::init<const std::string &>())
         .def(py::init([](const std::string &history, int) {
diff --git a/tests/test_class_sh_trampoline_unique_ptr.cpp b/tests/test_class_sh_trampoline_unique_ptr.cpp
index 141a6e8b57..12b2df93f3 100644
--- a/tests/test_class_sh_trampoline_unique_ptr.cpp
+++ b/tests/test_class_sh_trampoline_unique_ptr.cpp
@@ -8,6 +8,7 @@
 
 #include <cstdint>
 
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NS_VISIBILITY(pybind11_tests))
 namespace {
 
 class Class {
@@ -31,9 +32,11 @@ class Class {
 };
 
 } // namespace
+PYBIND11_NAMESPACE_END(pybind11_tests)
 
-PYBIND11_SMART_HOLDER_TYPE_CASTERS(Class)
+PYBIND11_SMART_HOLDER_TYPE_CASTERS(pybind11_tests::Class)
 
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NS_VISIBILITY(pybind11_tests))
 namespace {
 
 class PyClass : public Class, public py::trampoline_self_life_support {
@@ -46,8 +49,11 @@ class PyClass : public Class, public py::trampoline_self_life_support {
 };
 
 } // namespace
+PYBIND11_NAMESPACE_END(pybind11_tests)
 
 TEST_SUBMODULE(class_sh_trampoline_unique_ptr, m) {
+    using namespace pybind11_tests;
+
     py::classh<Class, PyClass>(m, "Class")
         .def(py::init<>())
         .def("set_val", &Class::setVal)
diff --git a/tests/test_class_sh_virtual_py_cpp_mix.cpp b/tests/test_class_sh_virtual_py_cpp_mix.cpp
index 2fa9990a22..d486a5682e 100644
--- a/tests/test_class_sh_virtual_py_cpp_mix.cpp
+++ b/tests/test_class_sh_virtual_py_cpp_mix.cpp
@@ -4,7 +4,7 @@
 
 #include <memory>
 
-namespace pybind11_tests {
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NS_VISIBILITY(pybind11_tests))
 namespace class_sh_virtual_py_cpp_mix {
 
 class Base {
@@ -44,7 +44,7 @@ struct CppDerivedVirtualOverrider : CppDerived, py::trampoline_self_life_support
 };
 
 } // namespace class_sh_virtual_py_cpp_mix
-} // namespace pybind11_tests
+PYBIND11_NAMESPACE_END(pybind11_tests)
 
 PYBIND11_SMART_HOLDER_TYPE_CASTERS(pybind11_tests::class_sh_virtual_py_cpp_mix::Base)
 PYBIND11_SMART_HOLDER_TYPE_CASTERS(pybind11_tests::class_sh_virtual_py_cpp_mix::CppDerivedPlain)
diff --git a/tests/test_custom_type_setup.cpp b/tests/test_custom_type_setup.cpp
index 42fae05d5d..057f4ad1f1 100644
--- a/tests/test_custom_type_setup.cpp
+++ b/tests/test_custom_type_setup.cpp
@@ -13,14 +13,19 @@
 
 namespace py = pybind11;
 
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NS_VISIBILITY(pybind11_tests))
 namespace {
 
 struct OwnsPythonObjects {
     py::object value = py::none();
 };
+
 } // namespace
+PYBIND11_NAMESPACE_END(pybind11_tests)
 
 TEST_SUBMODULE(custom_type_setup, m) {
+    using namespace pybind11_tests;
+
     py::class_<OwnsPythonObjects> cls(
         m, "OwnsPythonObjects", py::custom_type_setup([](PyHeapTypeObject *heap_type) {
             auto *type = &heap_type->ht_type;
diff --git a/tests/test_exceptions.cpp b/tests/test_exceptions.cpp
index 3ec999d1dc..25f48f7802 100644
--- a/tests/test_exceptions.cpp
+++ b/tests/test_exceptions.cpp
@@ -15,6 +15,8 @@
 #include <stdexcept>
 #include <utility>
 
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NS_VISIBILITY(pybind11_tests))
+
 // A type that should be raised as an exception in Python
 class MyException : public std::exception {
 public:
@@ -110,7 +112,11 @@ std::string error_already_set_what(const py::object &exc_type, const py::object
     return py::error_already_set().what();
 }
 
+PYBIND11_NAMESPACE_END(pybind11_tests)
+
 TEST_SUBMODULE(exceptions, m) {
+    using namespace pybind11_tests;
+
     m.def("throw_std_exception",
           []() { throw std::runtime_error("This exception was intentionally thrown."); });
 
diff --git a/tests/test_exceptions.h b/tests/test_exceptions.h
index 03684b89fa..adad7c6c4e 100644
--- a/tests/test_exceptions.h
+++ b/tests/test_exceptions.h
@@ -5,9 +5,13 @@
 
 // shared exceptions for cross_module_tests
 
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NS_VISIBILITY(pybind11_tests))
+
 class PYBIND11_EXPORT_EXCEPTION shared_exception : public pybind11::builtin_exception {
 public:
     using builtin_exception::builtin_exception;
     explicit shared_exception() : shared_exception("") {}
     void set_error() const override { PyErr_SetString(PyExc_RuntimeError, what()); }
 };
+
+PYBIND11_NAMESPACE_END(pybind11_tests)
diff --git a/tests/test_numpy_array.cpp b/tests/test_numpy_array.cpp
index 69ddbe1ef2..81639f06ec 100644
--- a/tests/test_numpy_array.cpp
+++ b/tests/test_numpy_array.cpp
@@ -15,6 +15,8 @@
 #include <cstdint>
 #include <utility>
 
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NS_VISIBILITY(pybind11_tests))
+
 // Size / dtype checks.
 struct DtypeCheck {
     py::dtype numpy{};
@@ -159,7 +161,11 @@ py::handle auxiliaries(T &&r, T2 &&r2) {
 // note: declaration at local scope would create a dangling reference!
 static int data_i = 42;
 
+PYBIND11_NAMESPACE_END(pybind11_tests)
+
 TEST_SUBMODULE(numpy_array, sm) {
+    using namespace pybind11_tests;
+
     try {
         py::module_::import("numpy");
     } catch (const py::error_already_set &) {
diff --git a/tests/test_pytypes.cpp b/tests/test_pytypes.cpp
index cb81007c37..e2286240d2 100644
--- a/tests/test_pytypes.cpp
+++ b/tests/test_pytypes.cpp
@@ -11,7 +11,7 @@
 
 #include <utility>
 
-namespace external {
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NS_VISIBILITY(external))
 namespace detail {
 bool check(PyObject *o) { return PyFloat_Check(o) != 0; }
 
@@ -37,7 +37,7 @@ class float_ : public py::object {
 
     double get_value() const { return PyFloat_AsDouble(this->ptr()); }
 };
-} // namespace external
+PYBIND11_NAMESPACE_END(external)
 
 TEST_SUBMODULE(pytypes, m) {
     // test_bool
diff --git a/tools/pybind11NewTools.cmake b/tools/pybind11NewTools.cmake
index abba0fe0e2..52306d0cfa 100644
--- a/tools/pybind11NewTools.cmake
+++ b/tools/pybind11NewTools.cmake
@@ -203,19 +203,6 @@ function(pybind11_add_module target_name)
     target_link_libraries(${target_name} PRIVATE pybind11::windows_extras)
   endif()
 
-  # -fvisibility=hidden is required to allow multiple modules compiled against
-  # different pybind versions to work properly, and for some features (e.g.
-  # py::module_local).  We force it on everything inside the `pybind11`
-  # namespace; also turning it on for a pybind module compilation here avoids
-  # potential warnings or issues from having mixed hidden/non-hidden types.
-  if(NOT DEFINED CMAKE_CXX_VISIBILITY_PRESET)
-    set_target_properties(${target_name} PROPERTIES CXX_VISIBILITY_PRESET "hidden")
-  endif()
-
-  if(NOT DEFINED CMAKE_CUDA_VISIBILITY_PRESET)
-    set_target_properties(${target_name} PROPERTIES CUDA_VISIBILITY_PRESET "hidden")
-  endif()
-
   # If we don't pass a WITH_SOABI or WITHOUT_SOABI, use our own default handling of extensions
   if(NOT ARG_WITHOUT_SOABI AND NOT "WITH_SOABI" IN_LIST ARG_UNPARSED_ARGUMENTS)
     pybind11_extension(${target_name})
diff --git a/tools/pybind11Tools.cmake b/tools/pybind11Tools.cmake
index 5535e872f3..542fd92d68 100644
--- a/tools/pybind11Tools.cmake
+++ b/tools/pybind11Tools.cmake
@@ -183,19 +183,6 @@ function(pybind11_add_module target_name)
 
   pybind11_extension(${target_name})
 
-  # -fvisibility=hidden is required to allow multiple modules compiled against
-  # different pybind versions to work properly, and for some features (e.g.
-  # py::module_local).  We force it on everything inside the `pybind11`
-  # namespace; also turning it on for a pybind module compilation here avoids
-  # potential warnings or issues from having mixed hidden/non-hidden types.
-  if(NOT DEFINED CMAKE_CXX_VISIBILITY_PRESET)
-    set_target_properties(${target_name} PROPERTIES CXX_VISIBILITY_PRESET "hidden")
-  endif()
-
-  if(NOT DEFINED CMAKE_CUDA_VISIBILITY_PRESET)
-    set_target_properties(${target_name} PROPERTIES CUDA_VISIBILITY_PRESET "hidden")
-  endif()
-
   if(ARG_NO_EXTRAS)
     return()
   endif()