diff --git a/libs/util/test/Makefile.am b/libs/util/test/Makefile.am
index e858ed6ef..8560f3e18 100644
--- a/libs/util/test/Makefile.am
+++ b/libs/util/test/Makefile.am
@@ -3,7 +3,8 @@ AUTOMAKE_OPTIONS= foreign
 INCLUDES= -I$(top_srcdir)/include
 
 check_PROGRAMS= \
-	test-dq test-half test-mat3 test-mat4 test-qfs test-quat test-vrect
+	test-dq test-half test-mat3 test-mat4 test-qfs test-quat test-set \
+	test-vrect
 
 test_dq_SOURCES=test-dq.c
 test_dq_LDADD=$(top_builddir)/libs/util/libQFutil.la
@@ -29,6 +30,10 @@ test_quat_SOURCES=test-quat.c
 test_quat_LDADD=$(top_builddir)/libs/util/libQFutil.la
 test_quat_DEPENDENCIES=$(top_builddir)/libs/util/libQFutil.la
 
+test_set_SOURCES=test-set.c
+test_set_LDADD=$(top_builddir)/libs/util/libQFutil.la
+test_set_DEPENDENCIES=$(top_builddir)/libs/util/libQFutil.la
+
 test_vrect_SOURCES=test-vrect.c
 test_vrect_LDADD=$(top_builddir)/libs/util/libQFutil.la
 test_vrect_DEPENDENCIES=$(top_builddir)/libs/util/libQFutil.la
diff --git a/libs/util/test/test-set.c b/libs/util/test/test-set.c
new file mode 100644
index 000000000..44431146d
--- /dev/null
+++ b/libs/util/test/test-set.c
@@ -0,0 +1,91 @@
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+#include <stdio.h>
+#include <string.h>
+
+#include "QF/set.h"
+
+typedef set_t *(*setup_func) (void);
+typedef set_t *(*test_func) (set_t *s1, set_t *s2);
+
+static set_t *
+make_empty1 (void)
+{
+	set_t      *set = set_new ();
+	return set;
+}
+
+static set_t *
+make_empty2 (void)
+{
+	set_t      *set = set_new ();
+	return set_empty (set);
+}
+
+static set_t *
+make_everything (void)
+{
+	set_t      *set = set_new ();
+	return set_everything (set);
+}
+
+static set_t *
+make_empty_invert (void)
+{
+	set_t      *set = set_new ();
+	return set_invert (set);
+}
+
+static set_t *
+make_everything_invert (void)
+{
+	set_t      *set = set_new ();
+	set_everything (set);
+	return set_invert (set);
+}
+
+struct {
+	setup_func set1;
+	setup_func set2;
+	test_func  test;
+	const char *expect;
+} tests[] = {
+	{make_empty1, 0, 0, "[empty]"},
+	{make_empty2, 0, 0, "[empty]"},
+	{make_everything, 0, 0, "[everything]"},
+	{make_empty_invert, 0, 0, "[everything]"},
+	{make_everything_invert, 0, 0, "[empty]"},
+};
+#define num_tests (sizeof (tests) / sizeof (tests[0]))
+
+int
+main (int argc, const char **argv)
+{
+	size_t      i;
+	int         res = 0;
+
+	for (i = 0; i < num_tests; i++) {
+		set_t      *s1, *s2 = 0;
+		const char *set_str;
+
+		s1 = tests[i].set1 ();
+		if (tests[i].set2)
+			s2 = tests[i].set2 ();
+		if (tests[i].test) {
+			if (tests[i].test (s1, s2) != s1) {
+				res |= 1;
+				printf ("test %d didn't return s1\n", (int) i);
+				continue;
+			}
+		}
+		set_str = set_as_string (s1);
+		if (strcmp (set_str, tests[i].expect)) {
+			res |= 1;
+			printf ("test %d failed\n", (int) i);
+			printf ("expect: %s\n", tests[i].expect);
+			printf ("got   : %s\n", set_str);
+		}
+	}
+	return res;
+}