diff --git a/tests/general/env-absent.c b/tests/general/env-absent.c
new file mode 100644
index 0000000..b5f6284
--- /dev/null
+++ b/tests/general/env-absent.c
@@ -0,0 +1,7 @@
+#include <stdlib.h>
+#include <stdio.h>
+
+int main(void) {
+    printf("HELLO = %s\n", getenv("HELLO"));
+    return 0;
+}
diff --git a/tests/general/env-absent.c.stdout.expected b/tests/general/env-absent.c.stdout.expected
new file mode 100644
index 0000000..f5614c3
--- /dev/null
+++ b/tests/general/env-absent.c.stdout.expected
@@ -0,0 +1 @@
+HELLO = (null)
diff --git a/tests/general/env.c b/tests/general/env.c
new file mode 100644
index 0000000..b5f6284
--- /dev/null
+++ b/tests/general/env.c
@@ -0,0 +1,7 @@
+#include <stdlib.h>
+#include <stdio.h>
+
+int main(void) {
+    printf("HELLO = %s\n", getenv("HELLO"));
+    return 0;
+}
diff --git a/tests/general/env.c.env b/tests/general/env.c.env
new file mode 100644
index 0000000..9be21df
--- /dev/null
+++ b/tests/general/env.c.env
@@ -0,0 +1 @@
+HELLO=hello
diff --git a/tests/general/env.c.stdout.expected b/tests/general/env.c.stdout.expected
new file mode 100644
index 0000000..b9a2a66
--- /dev/null
+++ b/tests/general/env.c.stdout.expected
@@ -0,0 +1 @@
+HELLO = hello
diff --git a/tests/testcase.sh b/tests/testcase.sh
index 61deefb..d2da956 100755
--- a/tests/testcase.sh
+++ b/tests/testcase.sh
@@ -41,9 +41,16 @@ else
   stdin="/dev/null"
 fi
 
+# Determine any environment variables to set.
+if [ -e "$input.env" ]; then
+    env=$(sed -e 's/^/--env /' < "$input.env")
+else
+    env=""
+fi
+
 # Run the test, capturing stdout, stderr, and the exit status.
 exit_status=0
-"$runwasi" "$wasm" \
+"$runwasi" $env "$wasm" \
     < "$stdin" \
     > "$stdout_observed" \
     2> "$stderr_observed" \