diff --git a/tests/pthread_test.cpp b/tests/pthread_test.cpp
index 04975df..9a474c0 100644
--- a/tests/pthread_test.cpp
+++ b/tests/pthread_test.cpp
@@ -18,6 +18,7 @@
 
 #include <errno.h>
 #include <pthread.h>
+#include <unistd.h>
 
 TEST(pthread, pthread_key_create) {
   pthread_key_t key;
@@ -26,3 +27,56 @@
   // Can't delete a key that's already been deleted.
   ASSERT_EQ(EINVAL, pthread_key_delete(key));
 }
+
+static void* IdFn(void* arg) {
+  return arg;
+}
+
+static void* SleepFn(void* arg) {
+  sleep(reinterpret_cast<unsigned int>(arg));
+  return NULL;
+}
+
+static void* JoinFn(void* arg) {
+  return reinterpret_cast<void*>(pthread_join(reinterpret_cast<pthread_t>(arg), NULL));
+}
+
+TEST(pthread, pthread_create) {
+  void* expected_result = reinterpret_cast<void*>(123);
+  // Can we create a thread?
+  pthread_t t;
+  ASSERT_EQ(0, pthread_create(&t, NULL, IdFn, expected_result));
+  // If we join, do we get the expected value back?
+  void* result;
+  ASSERT_EQ(0, pthread_join(t, &result));
+  ASSERT_EQ(expected_result, result);
+}
+
+TEST(pthread, pthread_no_join_after_detach) {
+  pthread_t t1;
+  ASSERT_EQ(0, pthread_create(&t1, NULL, SleepFn, reinterpret_cast<void*>(5)));
+
+  // After a pthread_detach...
+  ASSERT_EQ(0, pthread_detach(t1));
+
+  // ...pthread_join should fail.
+  void* result;
+  ASSERT_EQ(EINVAL, pthread_join(t1, &result));
+}
+
+TEST(pthread, pthread_no_op_detach_after_join) {
+  pthread_t t1;
+  ASSERT_EQ(0, pthread_create(&t1, NULL, SleepFn, reinterpret_cast<void*>(1)));
+
+  // If thread 2 is already waiting to join thread 1...
+  pthread_t t2;
+  ASSERT_EQ(0, pthread_create(&t2, NULL, JoinFn, reinterpret_cast<void*>(t1)));
+
+  // ...a call to pthread_detach on thread 1 will "succeed"...
+  ASSERT_EQ(0, pthread_detach(t1));
+
+  // ...but the join still goes ahead.
+  void* join_result;
+  ASSERT_EQ(0, pthread_join(t2, &join_result));
+  ASSERT_EQ(EINVAL, reinterpret_cast<int>(join_result));
+}