diff --git a/Code.ts b/Code.ts
index 1cbdd18..eb2e497 100644
--- a/Code.ts
+++ b/Code.ts
@@ -1,3 +1,7 @@
+const DOCUMENT_TEMPLATE_IDS = {
+  Certification: '1V0uMuM80BGpjpdt1AmuzlU97tDI_u-y2rOfdl4tkqmc',
+};
+
 const OUTPUT_FOLDER_ID = '1ROyJXk-QANTHM6Jiw0ne3EQiR1f2UsLr';
 
 function onOpen() {
@@ -80,7 +84,14 @@ function generateForRow(
 ) {
   const row = spreadsheetRowToObject(spreadsheet.getActiveSheet(), row_num);
 
-  const template_doc = DocumentApp.openById(row['Template ID']);
+  if (!(row['Document Type'] in DOCUMENT_TEMPLATE_IDS))
+    throw new Error(`${row['Document Type']} is not a valid type of document!`);
+
+  const template_doc = DocumentApp.openById(
+    DOCUMENT_TEMPLATE_IDS[
+      row['Document Type'] as keyof typeof DOCUMENT_TEMPLATE_IDS
+    ]
+  );
 
   const source_file = DriveApp.getFileById(row['Document ID']);
   const out_folder = DriveApp.getFolderById(OUTPUT_FOLDER_ID);