diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1c047a8637f..324cf840bb4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -18,6 +18,17 @@ cmake_minimum_required(
   FATAL_ERROR
 )
 
+## For experimental purpose only!
+message(
+  WARNING
+  "Experimental build: Changes the default char type to unsigned!"
+)
+if(CMAKE_GENERATOR MATCHES "Visual Studio")
+  add_compile_options(/J)
+else()
+  add_compile_options(-funsigned-char)
+endif()
+
 #
 # Now enumerate specific policies newer than ITK_NEWEST_VALIDATED_POLICIES_VERSION
 # that may need to be individually set to NEW/OLD
diff --git a/Modules/IO/HDF5/src/itkHDF5ImageIO.cxx b/Modules/IO/HDF5/src/itkHDF5ImageIO.cxx
index 6daf59a87ee..0fc128d5185 100644
--- a/Modules/IO/HDF5/src/itkHDF5ImageIO.cxx
+++ b/Modules/IO/HDF5/src/itkHDF5ImageIO.cxx
@@ -24,6 +24,7 @@
 #include "itkMakeUniqueForOverwrite.h"
 
 #include <algorithm>
+#include <type_traits> // For is_signed_v.
 
 namespace itk
 {
@@ -83,19 +84,20 @@ GetType()
   }
 
 GetH5TypeSpecialize(float, H5::PredType::NATIVE_FLOAT) GetH5TypeSpecialize(double, H5::PredType::NATIVE_DOUBLE)
+  GetH5TypeSpecialize(signed char, H5::PredType::NATIVE_SCHAR) GetH5TypeSpecialize(char, H5::PredType::NATIVE_CHAR)
+    GetH5TypeSpecialize(unsigned char, H5::PredType::NATIVE_UCHAR)
 
-  GetH5TypeSpecialize(char, H5::PredType::NATIVE_CHAR) GetH5TypeSpecialize(unsigned char, H5::PredType::NATIVE_UCHAR)
+      GetH5TypeSpecialize(short, H5::PredType::NATIVE_SHORT)
+        GetH5TypeSpecialize(short unsigned int, H5::PredType::NATIVE_USHORT)
 
-    GetH5TypeSpecialize(short, H5::PredType::NATIVE_SHORT)
-      GetH5TypeSpecialize(short unsigned int, H5::PredType::NATIVE_USHORT)
+          GetH5TypeSpecialize(int, H5::PredType::NATIVE_INT)
+            GetH5TypeSpecialize(unsigned int, H5::PredType::NATIVE_UINT)
 
-        GetH5TypeSpecialize(int, H5::PredType::NATIVE_INT) GetH5TypeSpecialize(unsigned int, H5::PredType::NATIVE_UINT)
+              GetH5TypeSpecialize(long, H5::PredType::NATIVE_LONG)
+                GetH5TypeSpecialize(long unsigned int, H5::PredType::NATIVE_ULONG)
 
-          GetH5TypeSpecialize(long, H5::PredType::NATIVE_LONG)
-            GetH5TypeSpecialize(long unsigned int, H5::PredType::NATIVE_ULONG)
-
-              GetH5TypeSpecialize(long long, H5::PredType::NATIVE_LLONG)
-                GetH5TypeSpecialize(unsigned long long, H5::PredType::NATIVE_ULLONG)
+                  GetH5TypeSpecialize(long long, H5::PredType::NATIVE_LLONG)
+                    GetH5TypeSpecialize(unsigned long long, H5::PredType::NATIVE_ULLONG)
 
 /* The following types are not implemented.  This comment serves
  * to indicate that the full complement of possible H5::PredType
@@ -105,7 +107,7 @@ GetH5TypeSpecialize(float, H5::PredType::NATIVE_FLOAT) GetH5TypeSpecialize(doubl
 
 #undef GetH5TypeSpecialize
 
-                  inline IOComponentEnum PredTypeToComponentType(H5::DataType & type)
+                      inline IOComponentEnum PredTypeToComponentType(H5::DataType & type)
 {
   if (type == H5::PredType::NATIVE_UCHAR)
   {
@@ -113,7 +115,11 @@ GetH5TypeSpecialize(float, H5::PredType::NATIVE_FLOAT) GetH5TypeSpecialize(doubl
   }
   if (type == H5::PredType::NATIVE_CHAR)
   {
-    return IOComponentEnum::CHAR;
+    return std::is_signed_v<char> ? IOComponentEnum::SCHAR : IOComponentEnum::UCHAR;
+  }
+  else if (type == H5::PredType::NATIVE_SCHAR)
+  {
+    return IOComponentEnum::SCHAR;
   }
   else if (type == H5::PredType::NATIVE_USHORT)
   {
@@ -166,7 +172,7 @@ ComponentToPredType(IOComponentEnum cType)
     case IOComponentEnum::UCHAR:
       return H5::PredType::NATIVE_UCHAR;
     case IOComponentEnum::SCHAR:
-      return H5::PredType::NATIVE_CHAR;
+      return H5::PredType::NATIVE_SCHAR;
     case IOComponentEnum::USHORT:
       return H5::PredType::NATIVE_USHORT;
     case IOComponentEnum::SHORT:
@@ -784,6 +790,10 @@ HDF5ImageIO::ReadImageInformation()
       {
         this->StoreMetaData<char>(&metaDict, localMetaDataName, name, metaDataDims[0]);
       }
+      else if (metaDataType == H5::PredType::NATIVE_SCHAR)
+      {
+        this->StoreMetaData<signed char>(&metaDict, localMetaDataName, name, metaDataDims[0]);
+      }
       else if (metaDataType == H5::PredType::NATIVE_UCHAR)
       {
         if (doesAttrExist(metaDataSet, "isBool"))
diff --git a/Modules/IO/MeshVTK/src/itkVTKPolyDataMeshIO.cxx b/Modules/IO/MeshVTK/src/itkVTKPolyDataMeshIO.cxx
index 8ad42590a37..04c7f28e210 100644
--- a/Modules/IO/MeshVTK/src/itkVTKPolyDataMeshIO.cxx
+++ b/Modules/IO/MeshVTK/src/itkVTKPolyDataMeshIO.cxx
@@ -828,7 +828,7 @@ VTKPolyDataMeshIO::ReadMeshInformation()
   }                                                             \
   case IOComponentEnum::SCHAR:                                  \
   {                                                             \
-    function(param, static_cast<char *>(buffer));               \
+    function(param, static_cast<signed char *>(buffer));        \
     break;                                                      \
   }                                                             \
   case IOComponentEnum::USHORT:                                 \
@@ -1696,7 +1696,7 @@ VTKPolyDataMeshIO::WriteMeshInformation()
   }                                                                                    \
   case IOComponentEnum::SCHAR:                                                         \
   {                                                                                    \
-    function(outputFile, static_cast<char *>(buffer), " char");                        \
+    function(outputFile, static_cast<signed char *>(buffer), " char");                 \
     break;                                                                             \
   }                                                                                    \
   case IOComponentEnum::USHORT:                                                        \
@@ -1819,8 +1819,8 @@ VTKPolyDataMeshIO::WritePoints(void * buffer)
   }                                                                   \
   case IOComponentEnum::SCHAR:                                        \
   {                                                                   \
-    UpdateCellInformation(static_cast<char *>(buffer));               \
-    function(outputFile, static_cast<char *>(buffer));                \
+    UpdateCellInformation(static_cast<signed char *>(buffer));        \
+    function(outputFile, static_cast<signed char *>(buffer));         \
     break;                                                            \
   }                                                                   \
   case IOComponentEnum::USHORT:                                       \