diff --git a/in2lambda/json_convert/json_convert.py b/in2lambda/json_convert/json_convert.py
index 270ef38..aa9548f 100644
--- a/in2lambda/json_convert/json_convert.py
+++ b/in2lambda/json_convert/json_convert.py
@@ -15,6 +15,8 @@
 def _zip_sorted_folder(folder_path, zip_path):
     """Zips the contents of a folder, preserving the directory structure.
 
+    Lambda Feedback imports questions in archive order, so the files are sorted.
+
     Args:
         folder_path: The path to the folder to zip.
         zip_path: The path where the zip file will be created.
@@ -187,6 +189,7 @@ def converter(SetQuestions: Set, output_dir: str) -> None:
         # Output file
         filename = (
             "question_"
+            # Alphabetical order is question order for up to 1000 questions
             + str(i).zfill(3)
             + "_"
             + re.sub(r"[^\w\-_.]", "_", output["title"].strip())
diff --git a/tests/fixtures/exports/README.md b/tests/fixtures/exports/README.md
index b98f2a0..b9a8a7a 100644
--- a/tests/fixtures/exports/README.md
+++ b/tests/fixtures/exports/README.md
@@ -24,7 +24,7 @@ answers, worked solutions, structured tutorials and the chatbot.
 
 | key | meaning |
 |---|---|
-| `orderNumber` | position in the set, from 0; matches the filename |
+| `orderNumber` | position in the set, from 0; matches the filename. The importer currently follows archive order, so the two must agree |
 | `title` | shown to students |
 | `skill` | difficulty (exports use 1/3 and 2/3) |
 | `guidance` | a sentence to students about the question's purpose |
diff --git a/tests/test_export_keys.py b/tests/test_export_keys.py
index eaadb08..ea8b9e6 100644
--- a/tests/test_export_keys.py
+++ b/tests/test_export_keys.py
@@ -7,6 +7,7 @@
 """
 
 import json
+import zipfile
 from pathlib import Path
 
 from in2lambda.api.part import Part
@@ -93,3 +94,13 @@ def test_each_response_type_writes_the_settings_of_a_real_export() -> None:
                     evaluation_function=""
                 )
                 assert set(written._config() or {}) == set(response["config"] or {})
+
+
+def test_the_zip_lists_questions_in_order_number_order(tmp_path) -> None:
+    titles = ["Zeta", "Alpha", "Mu"]
+    Set(questions=[Question(title=t) for t in titles]).to_json(str(tmp_path))
+
+    with zipfile.ZipFile(tmp_path / "set.zip") as zf:
+        names = [n for n in zf.namelist() if n.startswith("question_")]
+        orders = [json.loads(zf.read(n))["orderNumber"] for n in names]
+    assert orders == list(range(len(titles)))