diff --git a/notes/test_names.org b/notes/test_names.org
index cf2bc18..d9e4f54 100644
--- a/notes/test_names.org
+++ b/notes/test_names.org
@@ -3,3 +3,4 @@ The autogen tests are the tests automatically generated to compare the output of
 
 - No prefix :: The test is run with the default settings (The upstream Emacs Org-mode determines the default settings)
 - la :: Short for "list alphabetic". Enables alphabetic plain lists.
+- t# :: Sets the tab-width to # (as in t4 sets the tab-width to 4).
diff --git a/org_mode_samples/greater_element/plain_list/tab_width_indentation_level.org b/org_mode_samples/greater_element/plain_list/tab_width_indentation_level.org
new file mode 100644
index 0000000..2dbe900
--- /dev/null
+++ b/org_mode_samples/greater_element/plain_list/tab_width_indentation_level.org
@@ -0,0 +1,5 @@
+# "lorem" is prefixed by a tab instead of spaces, so the editor's tab-width value determines whether lorem is a sibling of baz (tab-width 8), a sibling of bar (tab-width < 8), or a child of baz (tab-width > 8).
+1. foo
+ 1. bar
+        1. baz
+	1. lorem
diff --git a/src/compare/parse.rs b/src/compare/parse.rs
index 37cf4e1..0a35077 100644
--- a/src/compare/parse.rs
+++ b/src/compare/parse.rs
@@ -7,10 +7,12 @@ use crate::GlobalSettings;
 ///
 /// Currently only org-list-allow-alphabetical is supported.
 fn global_settings_elisp(global_settings: &GlobalSettings) -> String {
+    // This string concatenation is wildly inefficient but its only called in tests 🤷.
     let mut ret = "".to_owned();
     if global_settings.list_allow_alphabetical {
         ret += "(setq org-list-allow-alphabetical t)\n"
     }
+    ret += format!("(setq-default tab-width {})", global_settings.tab_width).as_str();
     ret
 }
 
diff --git a/tests/test_template b/tests/test_template
index dd1b569..1376ed3 100644
--- a/tests/test_template
+++ b/tests/test_template
@@ -1,3 +1,5 @@
+// TODO: Investigate writing a proc macro to make specifying these permutations easier.
+
 {expect_fail}
 #[test]
 fn autogen_{name}() -> Result<(), Box<dyn std::error::Error>> {{
@@ -20,3 +22,31 @@ fn autogen_la_{name}() -> Result<(), Box<dyn std::error::Error>> {{
     organic::compare::run_anonymous_compare_with_settings(org_contents.as_str(), &global_settings)?;
     Ok(())
 }}
+
+{expect_fail}
+#[test]
+fn autogen_t1_{name}() -> Result<(), Box<dyn std::error::Error>> {{
+    let org_path = "{path}";
+    let org_contents = std::fs::read_to_string(org_path).expect("Read org file.");
+    let global_settings = {{
+        let mut global_settings = organic::GlobalSettings::default();
+        global_settings.tab_width = 1;
+        global_settings
+    }};
+    organic::compare::run_anonymous_compare_with_settings(org_contents.as_str(), &global_settings)?;
+    Ok(())
+}}
+
+{expect_fail}
+#[test]
+fn autogen_t16_{name}() -> Result<(), Box<dyn std::error::Error>> {{
+    let org_path = "{path}";
+    let org_contents = std::fs::read_to_string(org_path).expect("Read org file.");
+    let global_settings = {{
+        let mut global_settings = organic::GlobalSettings::default();
+        global_settings.tab_width = 16;
+        global_settings
+    }};
+    organic::compare::run_anonymous_compare_with_settings(org_contents.as_str(), &global_settings)?;
+    Ok(())
+}}