diff --git a/CIME/build.py b/CIME/build.py
index 64f9a528b85..ed9ca2fd3ec 100644
--- a/CIME/build.py
+++ b/CIME/build.py
@@ -738,44 +738,53 @@ def _build_libraries(
         if not os.path.exists(shared_item):
             os.makedirs(shared_item)
 
-    mpilib = case.get_value("MPILIB")
-    ufs_driver = os.environ.get("UFS_DRIVER")
+    libs = list(dict.fromkeys(case.get_values("CASE_SUPPORT_LIBRARIES")))
+    logger.info(f"libs from case_support_libraries {libs}")
+    build_script = {}
     cpl_in_complist = False
     for l in complist:
         if "cpl" in l:
             cpl_in_complist = True
-    if ufs_driver:
-        logger.info("UFS_DRIVER is set to {}".format(ufs_driver))
-
-    # This is a bit hacky. The host model should define whatever
-    # shared libs it might need.
-    if ufs_driver and ufs_driver == "nems" and not cpl_in_complist:
-        libs = []
-    elif case.get_value("MODEL") == "cesm":
-        libs = ["gptl", "pio", "csm_share"]
-    elif case.get_value("MODEL") == "e3sm":
-        libs = ["gptl", "mct", "spio", "csm_share"]
-    else:
-        libs = ["gptl", "mct", "pio", "csm_share"]
+    # The libs variable should include a list of required support libraries.
+    # The following block is provided for backward compatibility.
+    if len(libs) < 1:
+        logger.warning(
+            "The model is using a deprecated method of determining support "
+            "libraries, please migrate to 'CASE_SUPPORT_LIBRARIES' variable."
+        )
+        mpilib = case.get_value("MPILIB")
+        ufs_driver = os.environ.get("UFS_DRIVER")
+        if ufs_driver:
+            logger.info("UFS_DRIVER is set to {}".format(ufs_driver))
+
+        # This is a bit hacky. The host model should define whatever
+        # shared libs it might need.
+        if ufs_driver and ufs_driver == "nems" and not cpl_in_complist:
+            libs = []
+        elif case.get_value("MODEL") == "cesm":
+            libs = ["gptl", "pio", "csm_share"]
+        elif case.get_value("MODEL") == "e3sm":
+            libs = ["gptl", "mct", "spio", "csm_share"]
+        else:
+            libs = ["gptl", "mct", "pio", "csm_share"]
 
-    libs.append("FTorch")
+        libs.append("FTorch")
 
-    if mpilib == "mpi-serial":
-        libs.insert(0, mpilib)
+        if mpilib == "mpi-serial":
+            libs.insert(0, mpilib)
 
-    if uses_kokkos(case) and comp_interface != "nuopc":
-        libs.append("ekat")
+        if uses_kokkos(case) and comp_interface != "nuopc":
+            libs.append("ekat")
 
-    # Build shared code of CDEPS nuopc data models
-    build_script = {}
-    if comp_interface == "nuopc" and (not ufs_driver or ufs_driver != "nems"):
-        libs.append("CDEPS")
+        # Build shared code of CDEPS nuopc data models
+        if comp_interface == "nuopc" and (not ufs_driver or ufs_driver != "nems"):
+            libs.append("CDEPS")
 
-    ocn_model = case.get_value("COMP_OCN")
+        ocn_model = case.get_value("COMP_OCN")
 
-    atm_dycore = case.get_value("CAM_DYCORE")
-    if ocn_model == "mom" or (atm_dycore and atm_dycore == "fv3"):
-        libs.append("FMS")
+        atm_dycore = case.get_value("CAM_DYCORE")
+        if ocn_model == "mom" or (atm_dycore and atm_dycore == "fv3"):
+            libs.append("FMS")
 
     files = Files(comp_interface=comp_interface)
     for lib in libs:
diff --git a/CIME/tests/test_unit_build.py b/CIME/tests/test_unit_build.py
new file mode 100644
index 00000000000..4d915283ee5
--- /dev/null
+++ b/CIME/tests/test_unit_build.py
@@ -0,0 +1,550 @@
+#!/usr/bin/env python3
+
+import os
+import unittest
+from unittest import mock
+from pathlib import Path
+
+from CIME import build
+from .utils import mock_case
+
+
+class TestBuild(unittest.TestCase):
+    @mock_case()
+    @mock.patch("CIME.build.uses_kokkos")
+    @mock.patch("CIME.build.generate_makefile_macro")  # no need for makefile macros
+    @mock.patch(
+        "CIME.build.Files"
+    )  # used to check expected behavior by checking libs variable
+    def test__build_libraries_case_support_libraries(
+        self, Files, _, uses_kokkos, case, caseroot, **kwargs
+    ):
+        uses_kokkos.return_value = False
+
+        exeroot = os.path.join(caseroot, "bld")
+        cimeroot = os.getcwd()
+        libroot = os.path.join(caseroot, "libs")
+        buildlist = []
+        complist = []
+
+        case.get_values = mock.MagicMock(
+            side_effect=[
+                ["gptl", "mct"],  # CASE_SUPPORT_LIBRARIES
+            ]
+        )
+
+        case.get_value = mock.MagicMock(
+            side_effect=[
+                "",  # SHAREDLIBROOT
+                False,  # TEST
+            ]
+        )
+
+        build._build_libraries(
+            case,
+            exeroot,
+            "shared",
+            caseroot,
+            cimeroot,
+            libroot,
+            "unique",
+            "gnu",
+            buildlist,
+            "mct",
+            complist,
+        )
+
+        get_value = Files.return_value.get_value
+
+        expected = [
+            mock.call("BUILD_LIB_FILE", {"lib": "gptl"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "mct"}, attribute_required=True),
+        ]
+
+        assert get_value.call_args_list == expected, get_value.call_args_list
+
+    @mock.patch.dict(os.environ, {"UFS_DRIVER": "nems"})
+    @mock_case()
+    @mock.patch("CIME.build.uses_kokkos")
+    @mock.patch("CIME.build.generate_makefile_macro")  # no need for makefile macros
+    @mock.patch(
+        "CIME.build.Files"
+    )  # used to check expected behavior by checking libs variable
+    def test__build_libraries_ufs_driver(
+        self, Files, _, uses_kokkos, case, caseroot, **kwargs
+    ):
+        uses_kokkos.return_value = False
+
+        exeroot = os.path.join(caseroot, "bld")
+        cimeroot = os.getcwd()
+        libroot = os.path.join(caseroot, "libs")
+        buildlist = ["cpl"]
+        complist = []
+
+        case.get_values = mock.MagicMock(
+            side_effect=[
+                [],  # CASE_SUPPORT_LIBRARIES
+            ]
+        )
+
+        case.get_value = mock.MagicMock(
+            side_effect=[
+                "openmpi",  # MPILIB
+                "e3sm",  # MODEL
+                "e3sm",  # MODEL
+                "",  # COMP_OCN
+                "",  # CAM_DYCORE
+                "",  # SHAREDLIBROOT
+                False,  # TEST
+            ]
+        )
+
+        build._build_libraries(
+            case,
+            exeroot,
+            "shared",
+            caseroot,
+            cimeroot,
+            libroot,
+            "unique",
+            "gnu",
+            buildlist,
+            "mct",
+            complist,
+        )
+
+        get_value = Files.return_value.get_value
+
+        expected = [
+            mock.call("BUILD_LIB_FILE", {"lib": "FTorch"}, attribute_required=True),
+        ]
+
+        assert get_value.call_args_list == expected, get_value.call_args_list
+
+    @mock_case()
+    @mock.patch("CIME.build.uses_kokkos")
+    @mock.patch("CIME.build.generate_makefile_macro")  # no need for makefile macros
+    @mock.patch(
+        "CIME.build.Files"
+    )  # used to check expected behavior by checking libs variable
+    def test__build_libraries_cesm_model(
+        self, Files, _, uses_kokkos, case, caseroot, **kwargs
+    ):
+        uses_kokkos.return_value = False
+
+        exeroot = os.path.join(caseroot, "bld")
+        cimeroot = os.getcwd()
+        libroot = os.path.join(caseroot, "libs")
+        buildlist = []
+        complist = []
+
+        case.get_values = mock.MagicMock(
+            side_effect=[
+                [],  # CASE_SUPPORT_LIBRARIES
+            ]
+        )
+
+        case.get_value = mock.MagicMock(
+            side_effect=[
+                "openmpi",  # MPILIB
+                "cesm",  # MODEL
+                "cesm",  # MODEL
+                "",  # COMP_OCN
+                "",  # CAM_DYCORE
+                "",  # SHAREDLIBROOT
+                False,  # TEST
+            ]
+        )
+
+        build._build_libraries(
+            case,
+            exeroot,
+            "shared",
+            caseroot,
+            cimeroot,
+            libroot,
+            "unique",
+            "gnu",
+            buildlist,
+            "mct",
+            complist,
+        )
+
+        get_value = Files.return_value.get_value
+
+        expected = [
+            mock.call("BUILD_LIB_FILE", {"lib": "gptl"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "pio"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "csm_share"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "FTorch"}, attribute_required=True),
+        ]
+
+        assert get_value.call_args_list == expected, get_value.call_args_list
+
+    @mock_case()
+    @mock.patch("CIME.build.uses_kokkos")
+    @mock.patch("CIME.build.generate_makefile_macro")  # no need for makefile macros
+    @mock.patch(
+        "CIME.build.Files"
+    )  # used to check expected behavior by checking libs variable
+    def test__build_libraries_other_model(
+        self, Files, _, uses_kokkos, case, caseroot, **kwargs
+    ):
+        uses_kokkos.return_value = False
+
+        exeroot = os.path.join(caseroot, "bld")
+        cimeroot = os.getcwd()
+        libroot = os.path.join(caseroot, "libs")
+        buildlist = []
+        complist = []
+
+        case.get_values = mock.MagicMock(
+            side_effect=[
+                [],  # CASE_SUPPORT_LIBRARIES
+            ]
+        )
+
+        case.get_value = mock.MagicMock(
+            side_effect=[
+                "openmpi",  # MPILIB
+                "new",  # MODEL
+                "new",  # MODEL
+                "",  # COMP_OCN
+                "",  # CAM_DYCORE
+                "",  # SHAREDLIBROOT
+                False,  # TEST
+            ]
+        )
+
+        build._build_libraries(
+            case,
+            exeroot,
+            "shared",
+            caseroot,
+            cimeroot,
+            libroot,
+            "unique",
+            "gnu",
+            buildlist,
+            "mct",
+            complist,
+        )
+
+        get_value = Files.return_value.get_value
+
+        expected = [
+            mock.call("BUILD_LIB_FILE", {"lib": "gptl"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "mct"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "pio"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "csm_share"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "FTorch"}, attribute_required=True),
+        ]
+
+        assert get_value.call_args_list == expected, get_value.call_args_list
+
+    @mock_case()
+    @mock.patch("CIME.build.uses_kokkos")
+    @mock.patch("CIME.build.generate_makefile_macro")  # no need for makefile macros
+    @mock.patch(
+        "CIME.build.Files"
+    )  # used to check expected behavior by checking libs variable
+    def test__build_libraries_mpi_serial(
+        self, Files, _, uses_kokkos, case, caseroot, **kwargs
+    ):
+        uses_kokkos.return_value = False
+
+        exeroot = os.path.join(caseroot, "bld")
+        cimeroot = os.getcwd()
+        libroot = os.path.join(caseroot, "libs")
+        buildlist = []
+        complist = []
+
+        case.get_values = mock.MagicMock(
+            side_effect=[
+                [],  # CASE_SUPPORT_LIBRARIES
+            ]
+        )
+
+        case.get_value = mock.MagicMock(
+            side_effect=[
+                "mpi-serial",  # MPILIB
+                "e3sm",  # MODEL
+                "e3sm",  # MODEL
+                "",  # COMP_OCN
+                "",  # CAM_DYCORE
+                "",  # SHAREDLIBROOT
+                False,  # TEST
+            ]
+        )
+
+        build._build_libraries(
+            case,
+            exeroot,
+            "shared",
+            caseroot,
+            cimeroot,
+            libroot,
+            "unique",
+            "gnu",
+            buildlist,
+            "mct",
+            complist,
+        )
+
+        get_value = Files.return_value.get_value
+
+        expected = [
+            mock.call("BUILD_LIB_FILE", {"lib": "mpi-serial"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "gptl"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "mct"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "spio"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "csm_share"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "FTorch"}, attribute_required=True),
+        ]
+
+        assert get_value.call_args_list == expected, get_value.call_args_list
+
+    @mock_case()
+    @mock.patch("CIME.build.uses_kokkos")
+    @mock.patch("CIME.build.generate_makefile_macro")  # no need for makefile macros
+    @mock.patch(
+        "CIME.build.Files"
+    )  # used to check expected behavior by checking libs variable
+    def test__build_libraries_use_kokkos(
+        self, Files, _, uses_kokkos, case, caseroot, **kwargs
+    ):
+        uses_kokkos.return_value = True
+
+        exeroot = os.path.join(caseroot, "bld")
+        cimeroot = os.getcwd()
+        libroot = os.path.join(caseroot, "libs")
+        buildlist = []
+        complist = []
+
+        case.get_values = mock.MagicMock(
+            side_effect=[
+                [],  # CASE_SUPPORT_LIBRARIES
+            ]
+        )
+
+        case.get_value = mock.MagicMock(
+            side_effect=[
+                "openmpi",  # MPILIB
+                "e3sm",  # MODEL
+                "e3sm",  # MODEL
+                "",  # COMP_OCN
+                "",  # CAM_DYCORE
+                "",  # SHAREDLIBROOT
+                False,  # TEST
+            ]
+        )
+
+        build._build_libraries(
+            case,
+            exeroot,
+            "shared",
+            caseroot,
+            cimeroot,
+            libroot,
+            "unique",
+            "gnu",
+            buildlist,
+            "mct",
+            complist,
+        )
+
+        get_value = Files.return_value.get_value
+
+        expected = [
+            mock.call("BUILD_LIB_FILE", {"lib": "gptl"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "mct"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "spio"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "csm_share"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "FTorch"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "ekat"}, attribute_required=True),
+        ]
+
+        assert get_value.call_args_list == expected, get_value.call_args_list
+
+    @mock_case()
+    @mock.patch("CIME.build.uses_kokkos")
+    @mock.patch("CIME.build.generate_makefile_macro")  # no need for makefile macros
+    @mock.patch(
+        "CIME.build.Files"
+    )  # used to check expected behavior by checking libs variable
+    def test__build_libraries_nuopc(
+        self, Files, _, uses_kokkos, case, caseroot, **kwargs
+    ):
+        uses_kokkos.return_value = False
+
+        exeroot = os.path.join(caseroot, "bld")
+        cimeroot = os.getcwd()
+        libroot = os.path.join(caseroot, "libs")
+        buildlist = []
+        complist = []
+
+        case.get_values = mock.MagicMock(
+            side_effect=[
+                [],  # CASE_SUPPORT_LIBRARIES
+            ]
+        )
+
+        case.get_value = mock.MagicMock(
+            side_effect=[
+                "openmpi",  # MPILIB
+                "e3sm",  # MODEL
+                "e3sm",  # MODEL
+                "",  # COMP_OCN
+                "",  # CAM_DYCORE
+                "",  # SHAREDLIBROOT
+                False,  # TEST
+            ]
+        )
+
+        build._build_libraries(
+            case,
+            exeroot,
+            "shared",
+            caseroot,
+            cimeroot,
+            libroot,
+            "unique",
+            "gnu",
+            buildlist,
+            "nuopc",
+            complist,
+        )
+
+        get_value = Files.return_value.get_value
+
+        expected = [
+            mock.call("BUILD_LIB_FILE", {"lib": "gptl"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "mct"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "spio"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "csm_share"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "FTorch"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "CDEPS"}, attribute_required=True),
+        ]
+
+        assert get_value.call_args_list == expected, get_value.call_args_list
+
+    @mock_case()
+    @mock.patch("CIME.build.uses_kokkos")
+    @mock.patch("CIME.build.generate_makefile_macro")  # no need for makefile macros
+    @mock.patch(
+        "CIME.build.Files"
+    )  # used to check expected behavior by checking libs variable
+    def test__build_libraries_fms(
+        self, Files, _, uses_kokkos, case, caseroot, **kwargs
+    ):
+        uses_kokkos.return_value = False
+
+        exeroot = os.path.join(caseroot, "bld")
+        cimeroot = os.getcwd()
+        libroot = os.path.join(caseroot, "libs")
+        buildlist = []
+        complist = []
+
+        case.get_values = mock.MagicMock(
+            side_effect=[
+                [],  # CASE_SUPPORT_LIBRARIES
+            ]
+        )
+
+        case.get_value = mock.MagicMock(
+            side_effect=[
+                "openmpi",  # MPILIB
+                "e3sm",  # MODEL
+                "e3sm",  # MODEL
+                "mom",  # COMP_OCN
+                "fv3",  # CAM_DYCORE
+                "",  # SHAREDLIBROOT
+                False,  # TEST
+            ]
+        )
+
+        build._build_libraries(
+            case,
+            exeroot,
+            "shared",
+            caseroot,
+            cimeroot,
+            libroot,
+            "unique",
+            "gnu",
+            buildlist,
+            "mct",
+            complist,
+        )
+
+        get_value = Files.return_value.get_value
+
+        expected = [
+            mock.call("BUILD_LIB_FILE", {"lib": "gptl"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "mct"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "spio"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "csm_share"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "FTorch"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "FMS"}, attribute_required=True),
+        ]
+
+        assert get_value.call_args_list == expected, get_value.call_args_list
+
+    @mock_case()
+    @mock.patch("CIME.build.uses_kokkos")
+    @mock.patch("CIME.build.generate_makefile_macro")  # no need for makefile macros
+    @mock.patch(
+        "CIME.build.Files"
+    )  # used to check expected behavior by checking libs variable
+    def test__build_libraries(self, Files, _, uses_kokkos, case, caseroot, **kwargs):
+        uses_kokkos.return_value = False
+
+        exeroot = os.path.join(caseroot, "bld")
+        cimeroot = os.getcwd()
+        libroot = os.path.join(caseroot, "libs")
+        buildlist = []
+        complist = []
+
+        case.get_values = mock.MagicMock(
+            side_effect=[
+                [],  # CASE_SUPPORT_LIBRARIES
+            ]
+        )
+
+        case.get_value = mock.MagicMock(
+            side_effect=[
+                "openmpi",  # MPILIB
+                "e3sm",  # MODEL
+                "e3sm",  # MODEL
+                "",  # COMP_OCN
+                "",  # CAM_DYCORE
+                "",  # SHAREDLIBROOT
+                False,  # TEST
+            ]
+        )
+
+        build._build_libraries(
+            case,
+            exeroot,
+            "shared",
+            caseroot,
+            cimeroot,
+            libroot,
+            "unique",
+            "gnu",
+            buildlist,
+            "mct",
+            complist,
+        )
+
+        get_value = Files.return_value.get_value
+
+        expected = [
+            mock.call("BUILD_LIB_FILE", {"lib": "gptl"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "mct"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "spio"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "csm_share"}, attribute_required=True),
+            mock.call("BUILD_LIB_FILE", {"lib": "FTorch"}, attribute_required=True),
+        ]
+
+        assert get_value.call_args_list == expected, get_value.call_args_list
diff --git a/CIME/tests/utils.py b/CIME/tests/utils.py
index 7679080eb01..951b5a8390e 100644
--- a/CIME/tests/utils.py
+++ b/CIME/tests/utils.py
@@ -165,7 +165,7 @@ def __str__(self):
         return ET.tostring(self.root.xml_element, encoding="unicode", method="xml")
 
 
-def mock_case(*args, empty_env=False, filename=None, **kwargs):
+def mock_case(*args, empty_env=False, filename=None, mock_set_value=False, **kwargs):
     if filename is None:
         filename = "env_test.xml"
 
@@ -176,6 +176,8 @@ def wrapper(self, read_xml, *args, **kwargs):
             with tempfile.TemporaryDirectory() as tempdir:
                 caseroot = f"{tempdir}/case"
                 with Case(caseroot, read_only=False) as case:
+                    case.flush = lambda: None
+
                     env = TestEnv()
                     env.filename = f"{os.getcwd()}/{filename}"
 
@@ -184,6 +186,9 @@ def wrapper(self, read_xml, *args, **kwargs):
 
                         case._env_entryid_files = [env]
 
+                    if mock_set_value:
+                        case.set_value = mock.MagicMock()
+
                     func(
                         self,
                         *args,
diff --git a/doc/source/ccs/model-configuration/config-files.rst b/doc/source/ccs/model-configuration/config-files.rst
index e1051ed4b4e..e8ce9c8dc60 100644
--- a/doc/source/ccs/model-configuration/config-files.rst
+++ b/doc/source/ccs/model-configuration/config-files.rst
@@ -59,7 +59,31 @@ schema            Path to a schema file that will be used to validate the conten
 
 Variables
 :::::::::
-These variables will define values or reference additional files to make up a models configuration.
+These variables define literal values.
+
+MODEL
+.....
+This variable defines the name of the Model.
+
+Entry
+'''''
+The following is an example entry for ``MODEL`` in ``config_files.xml``.
+
+Only a single value is required.
+
+.. code-block:: xml
+   
+   <entry id="MODEL">
+      <type>char</type>
+      <default_value>e3sm</default_value>
+      <group>case_der</group>
+      <file>env_case.xml</file>
+      <desc>model system name</desc>
+   </entry>
+
+Reference Variables
+:::::::::::::::::::
+These variables reference files containing additional variables.
 
 .. toctree::
    :maxdepth: 1
@@ -77,7 +101,6 @@ These variables will define values or reference additional files to make up a mo
    variables/grids.rst
    variables/inputdata.rst
    variables/machine.rst
-   variables/model.rst
    variables/namelist-definition.rst
    variables/pes.rst
    variables/pio.rst
diff --git a/doc/source/ccs/model-configuration/variables/build-lib.rst b/doc/source/ccs/model-configuration/variables/build-lib.rst
index 29506ab5c66..d49797d8d93 100644
--- a/doc/source/ccs/model-configuration/variables/build-lib.rst
+++ b/doc/source/ccs/model-configuration/variables/build-lib.rst
@@ -36,6 +36,7 @@ Each ``value`` corresponds to a library that can be built. The ``lib`` attribute
         <desc> path to buildlib script for the given library </desc>
     </entry>
 
+
 Build library
 --------------
 Implementing a ``buildlib`` for a component is as simple as creating a python file and defining a single function; *buildlib*.
@@ -78,4 +79,4 @@ Example
 
         cmake_args = get_standard_cmake_args(case, installpath)
 
-        run_bld_cmd_ensure_logging(f"cmake {cmake_args}", logger, from_dir=libdir)
\ No newline at end of file
+        run_bld_cmd_ensure_logging(f"cmake {cmake_args}", logger, from_dir=libdir)
diff --git a/doc/source/ccs/model-configuration/variables/component.rst b/doc/source/ccs/model-configuration/variables/component.rst
index feef4ec9802..189e5aec5ad 100644
--- a/doc/source/ccs/model-configuration/variables/component.rst
+++ b/doc/source/ccs/model-configuration/variables/component.rst
@@ -32,7 +32,6 @@ There will be multiple ``entry`` elements, one for each component supported by t
 
 Schema Definition
 -----------------
-
 The configuration is stored in ``config_component.xml`` under the components ``cime_config`` directory e.g. ``mosart/cime_config/config_component.xml``.
 This file will store multiple variables for the component defined using :ref:`*entry*<model-configuration-entry>` elements.
 Example contents of ``config_component.xml``.
@@ -71,9 +70,46 @@ help                Help text for the component.
             </help>
     </entry_id>
 
+Define support libraries
+------------------------
+This variable is a list of support libraries that should be built by the case.
+It is defined by the driver and component buildnml scripts and is used with ``BUILD_LIB_FILE`` to
+locate required buildlib scripts.  It is a list of libraries which will be built in list order so
+it is important that dependent libraries are identified.
+
+The ``CASE_SUPPORT_LIBRARIES`` variable should be defined in the drivers ``config_component.xml`` file as
+
+.. code-block:: xml
+
+   <entry id="CASE_SUPPORT_LIBRARIES">
+        <type>char</type>
+        <default_value></default_value>
+        <values>
+            <value cime_model="cesm">gptl,pio,csm_share,FTorch,CDEPS</value>
+        </values>
+        <group>build_def</group>
+        <file>env_build.xml</file>
+        <desc>Support libraries required</desc>
+   </entry>
+
+The components ``buildnml`` script can modify the variable and add a list of libraries needed by the given component.
+The list should be ordered so that a library comes after all of the libraries it depends on.
+
+The following is a small example of a ``buildnml`` script modifying ``CASE_SUPPORT_LIBRARIES``.
+
+.. code-block:: python
+    
+    def buildnml(case, caseroot, component):
+        ...
+        libs = case.get_value("CASE_SUPPORT_LIBRARIES")
+        mpilib = case.get_value("MPILIB")
+        if mpilib == "mpi-serial":
+            libs.insert(0, mpilib)
+        case.set_value("CASE_SUPPORT_LIBRARIES", ",".join(libs))
+        ...
+
 Triggering a rebuild
 --------------------
-
 It's the responsibility of a component to define which settings will require a component to be rebuilt.
 
 These triggers can be defined as follows.
diff --git a/doc/source/ccs/model-configuration/variables/model.rst b/doc/source/ccs/model-configuration/variables/model.rst
deleted file mode 100644
index 12caf58e81d..00000000000
--- a/doc/source/ccs/model-configuration/variables/model.rst
+++ /dev/null
@@ -1,27 +0,0 @@
-.. _model_config_model:
-
-MODEL
-=====
-
-.. contents::
-    :local:
-
-Overview
---------
-This variable defines the name of the Model.
-
-Entry
------
-The following is an example entry for ``MODEL`` in ``config_files.xml``.
-
-Only a single value is required.
-
-.. code-block:: xml
-    
-    <entry id="MODEL">
-        <type>char</type>
-        <default_value>e3sm</default_value>
-        <group>case_der</group>
-        <file>env_case.xml</file>
-        <desc>model system name</desc>
-    </entry>