diff --git a/Makefile b/Makefile
index d442b97b..8f8fb7fc 100644
--- a/Makefile
+++ b/Makefile
@@ -37,7 +37,8 @@ TEST_SRC = $(TEST_DIR)/unit-tests.scm \
 					 $(TEST_DIR)/srfi-60-tests.scm \
 					 $(TEST_DIR)/srfi-121-tests.scm \
 					 $(TEST_DIR)/srfi-128-162-tests.scm \
-					 $(TEST_DIR)/srfi-143-tests.scm
+					 $(TEST_DIR)/srfi-143-tests.scm \
+					 $(TEST_DIR)/threading.scm
 TESTS = $(basename $(TEST_SRC))
 
 # Primary rules (of interest to an end user)
diff --git a/tests/threading.scm b/tests/threading.scm
new file mode 100644
index 00000000..45584601
--- /dev/null
+++ b/tests/threading.scm
@@ -0,0 +1,22 @@
+;;;; Cyclone Scheme
+;;;; https://github.com/justinethier/cyclone
+;;;;
+;;;; Copyright (c) 2014-2021, Justin Ethier
+;;;; All rights reserved.
+;;;;
+;;;; This module contains unit tests for threading / SRFI 18.
+;;;;
+
+(import 
+  (scheme base)
+  (srfi 18)
+  (cyclone test))
+
+
+(test-group
+  "thread-join!"
+  (let ((t (thread-start! (make-thread (lambda () (expt 2 100))))))
+    (test (expt 2 100) (thread-join! t)))
+)
+
+(test-exit)