diff --git a/mu-plugins/central-hub/tests/phpunit/integration/config-store/loadConfigFromFilesystem.php b/mu-plugins/central-hub/tests/phpunit/integration/config-store/loadConfigFromFilesystem.php
new file mode 100644
index 00000000..905fb559
--- /dev/null
+++ b/mu-plugins/central-hub/tests/phpunit/integration/config-store/loadConfigFromFilesystem.php
@@ -0,0 +1,110 @@
+<?php
+/**
+ *  Tests for external API function loadConfigFromFilesystem()
+ *
+ * @package    spiralWebDb\centralHub\Tests\Integration\ConfigStore
+ * @since      1.3.0
+ * @author     Robert A. Gadon
+ * @link       https://github.com/rgadon107/cornerstone
+ * @license    GNU General Public License 2.0+
+ */
+
+namespace spiralWebDb\centralHub\Tests\Integration\ConfigStore;
+
+use Brain\Monkey;
+use function KnowTheCode\ConfigStore\_the_store;
+use function KnowTheCode\ConfigStore\loadConfigFromFilesystem;
+use spiralWebDb\Cornerstone\Tests\Integration\Test_Case;
+
+
+/**
+ * Class Tests_LoadConfigFromFilesystem
+ *
+ * @package spiralWebDb\centralHub\Tests\Integration\ConfigStore
+ * @group   config-store
+ */
+class Tests_LoadConfigFromFilesystem extends Test_Case {
+
+	/**
+	 * Test loadConfigFromFilesystem() should merge defaults with config and return a store key.
+	 */
+	public function test_should_merge_defaults_and_return_store_key() {
+		$path_to_file  = CENTRAL_HUB_ROOT_DIR . '/tests/phpunit/fixtures/test-cpt-config.php';
+		$defaults      = [
+			'aaa' => 37,
+			'eee' => 'Coding is fun!',
+		];
+		$merged_config = [
+			'aaa' => 'bbb',
+			'ccc' => 'ddd',
+			'eee' => 'Coding is fun!',
+		];
+
+		$this->assertSame( 'foo', loadConfigFromFilesystem( $path_to_file, $defaults ) );
+		$this->assertEquals( $merged_config, _the_store( 'foo' ) );
+	}
+
+	/**
+	 * Test loadConfigFromFilesystem() should store a config and return the store key.
+	 */
+	public function test_should_store_a_config_and_return_store_key() {
+		$path_to_file = CENTRAL_HUB_ROOT_DIR . '/tests/phpunit/fixtures/test-cpt-config.php';
+		$config       = [
+			'aaa' => 'bbb',
+			'ccc' => 'ddd',
+		];
+
+		$this->assertSame( 'foo', loadConfigFromFilesystem( $path_to_file ) );
+		$this->assertSame( $config, _the_store( 'foo' ) );
+	}
+
+	/**
+	 * Test loadConfigFromFilesystem() should overwrite stored configuration and return store key from
+	 * file configuration.
+	 */
+	public function test_should_overwrite_store_and_return_store_key_from_file_config() {
+		$path_to_file = CENTRAL_HUB_ROOT_DIR . '/tests/phpunit/fixtures/test-cpt-config.php';
+		$config       = [
+			'aaa' => 'bbb',
+			'ccc' => 'ddd',
+		];
+
+		$this->assertSame( 'foo', loadConfigFromFilesystem( $path_to_file ) );
+		$this->assertSame( 'foo', loadConfigFromFilesystem( $path_to_file ) );
+		$this->assertSame( $config, _the_store( 'foo' ) );
+	}
+
+	/**
+	 * Test loadConfigFromFilesystem() should overwrite stored configuration and return store key from
+	 * file configuration.
+	 */
+	public function test_should_throw_exception_when_no_store_key() {
+		$path_to_file = CENTRAL_HUB_ROOT_DIR . '/tests/phpunit/fixtures/config-with-params-only.php';
+		$this->expectException( \Exception::class );
+		$this->expectExceptionMessage(
+			sprintf( 'No store key exists in the %s configuration file.', $path_to_file )
+		);
+		Monkey\Functions\expect( '\KnowTheCode\ConfigStore\_merge_with_defaults' )->never();
+		Monkey\Functions\expect( '\KnowTheCode\ConfigStore\_the_store' )->never();
+
+		loadConfigFromFilesystem( $path_to_file );
+	}
+
+	/**
+	 * Test loadConfigFromFilesystem() should throw an Exception when the configuration parameters are empty.
+	 */
+	public function test_should_throw_exception_when_config_params_empty() {
+		$path_to_file = CENTRAL_HUB_ROOT_DIR . '/tests/phpunit/fixtures/config-with-store-key-only.php';
+		$this->expectException( \Exception::class );
+		$this->expectExceptionMessage(
+			sprintf(
+				'No configuration parameters exist for store key [foo] in the %s configuration file.',
+				$path_to_file
+			)
+		);
+		Monkey\Functions\expect( '\KnowTheCode\ConfigStore\_merge_with_defaults' )->never();
+		Monkey\Functions\expect( '\KnowTheCode\ConfigStore\_the_store' )->never();
+
+		loadConfigFromFilesystem( $path_to_file );
+	}
+}
diff --git a/mu-plugins/central-hub/tests/phpunit/unit/config-store/_loadConfigFromFilesystem.php b/mu-plugins/central-hub/tests/phpunit/unit/config-store/_loadConfigFromFilesystem.php
index cd1b8acd..681055ba 100644
--- a/mu-plugins/central-hub/tests/phpunit/unit/config-store/_loadConfigFromFilesystem.php
+++ b/mu-plugins/central-hub/tests/phpunit/unit/config-store/_loadConfigFromFilesystem.php
@@ -16,12 +16,12 @@
 use spiralWebDb\Cornerstone\Tests\Unit\Test_Case;
 
 /**
- * Class Tests_LoadConfigFromFilesystem
+ * Class Tests__LoadConfigFromFilesystem
  *
  * @package spiralWebDb\centralHub\Tests\Unit\ConfigStore
  * @group   config-store
  */
-class Tests_LoadConfigFromFilesystem extends Test_Case {
+class Tests__LoadConfigFromFilesystem extends Test_Case {
 
 	/**
 	 * Prepares the test environment before each test.
diff --git a/mu-plugins/central-hub/tests/phpunit/unit/config-store/loadConfigFromFilesystem.php b/mu-plugins/central-hub/tests/phpunit/unit/config-store/loadConfigFromFilesystem.php
new file mode 100644
index 00000000..32507fa1
--- /dev/null
+++ b/mu-plugins/central-hub/tests/phpunit/unit/config-store/loadConfigFromFilesystem.php
@@ -0,0 +1,114 @@
+<?php
+/**
+ *  Tests for external API function loadConfigFromFilesystem()
+ *
+ * @package    spiralWebDb\centralHub\Tests\Unit\ConfigStore
+ * @since      1.3.0
+ * @author     Robert A. Gadon
+ * @link       https://github.com/rgadon107/cornerstone
+ * @license    GNU General Public License 2.0+
+ */
+
+namespace spiralWebDb\centralHub\Tests\Unit\ConfigStore;
+
+use Brain\Monkey;
+use function KnowTheCode\ConfigStore\loadConfigFromFilesystem;
+use spiralWebDb\Cornerstone\Tests\Unit\Test_Case;
+
+/**
+ * Class Tests_LoadConfigFromFilesystem
+ *
+ * @package spiralWebDb\centralHub\Tests\Unit\ConfigStore
+ * @group   config-store
+ */
+class Tests_LoadConfigFromFilesystem extends Test_Case {
+
+	/**
+	 * Prepares the test environment before each test.
+	 */
+	protected function setUp() {
+		parent::setUp();
+
+		require_once CENTRAL_HUB_ROOT_DIR . '/src/config-store/api.php';
+	}
+
+	/**
+	 * Test loadConfigFromFilesystem() should merge defaults with config and return a store key.
+	 */
+	public function test_should_merge_defaults_and_return_store_key() {
+		$path_to_file  = CENTRAL_HUB_ROOT_DIR . '/tests/phpunit/fixtures/test-cpt-config.php';
+		$defaults      = [
+			'aaa' => 37,
+			'eee' => 'Coding is fun!',
+		];
+		$config        = [
+			'aaa' => 'bbb',
+			'ccc' => 'ddd',
+		];
+		$merged_config = [
+			'aaa' => 'bbb',
+			'ccc' => 'ddd',
+			'eee' => 'Coding is fun!',
+		];
+		Monkey\Functions\expect( '\KnowTheCode\ConfigStore\_load_config_from_filesystem' )
+			->once()
+			->with( $path_to_file )
+			->andReturn( [ 'foo', $config ] );
+		Monkey\Functions\expect( '\KnowTheCode\ConfigStore\_merge_with_defaults' )
+			->once()
+			->with( $config, $defaults )
+			->andReturn( $merged_config );
+		Monkey\Functions\expect( '\KnowTheCode\ConfigStore\_the_store' )
+			->once()
+			->with( 'foo', $merged_config )
+			->andReturn( true );
+
+		$this->assertSame( 'foo', loadConfigFromFilesystem( $path_to_file, $defaults ) );
+	}
+
+	/**
+	 * Test loadConfigFromFilesystem() should store a config and return the store key.
+	 */
+	public function test_should_store_a_config_and_return_store_key() {
+		$path_to_file = CENTRAL_HUB_ROOT_DIR . '/tests/phpunit/fixtures/test-cpt-config.php';
+		$config       = [
+			'aaa' => 'bbb',
+			'ccc' => 'ddd',
+		];
+		Monkey\Functions\expect( '\KnowTheCode\ConfigStore\_load_config_from_filesystem' )
+			->once()
+			->with( $path_to_file )
+			->andReturn( [ 'foo', $config ] );
+		Monkey\Functions\expect( '\KnowTheCode\ConfigStore\_merge_with_defaults' )->never();
+		Monkey\Functions\expect( '\KnowTheCode\ConfigStore\_the_store' )
+			->once()
+			->with( 'foo', $config )
+			->andReturn( true );
+
+		$this->assertSame( 'foo', loadConfigFromFilesystem( $path_to_file ) );
+	}
+
+	/**
+	 * Test loadConfigFromFilesystem() should overwrite stored configuration and return store key from
+	 * file configuration.
+	 */
+	public function test_should_overwrite_store_and_return_store_key_from_file_config() {
+		$path_to_file = CENTRAL_HUB_ROOT_DIR . '/tests/phpunit/fixtures/test-cpt-config.php';
+		$config       = [
+			'aaa' => 'bbb',
+			'ccc' => 'ddd',
+		];
+		Monkey\Functions\expect( '\KnowTheCode\ConfigStore\_load_config_from_filesystem' )
+			->twice()
+			->with( $path_to_file )
+			->andReturn( [ 'foo', $config ] );
+		Monkey\Functions\expect( '\KnowTheCode\ConfigStore\_merge_with_defaults' )->never();
+		Monkey\Functions\expect( '\KnowTheCode\ConfigStore\_the_store' )
+			->twice()
+			->with( 'foo', $config )
+			->andReturn( true );
+
+		$this->assertSame( 'foo', loadConfigFromFilesystem( $path_to_file ) );
+		$this->assertSame( 'foo', loadConfigFromFilesystem( $path_to_file ) );
+	}
+}