diff --git a/package-lock.json b/package-lock.json
index 8b3bf48..f9501e4 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -37,9 +37,9 @@
             "dev": true
         },
         "@types/mocha": {
-            "version": "8.2.1",
-            "resolved": "https://registry.npmjs.org/@types/mocha/-/mocha-8.2.1.tgz",
-            "integrity": "sha512-NysN+bNqj6E0Hv4CTGWSlPzMW6vTKjDpOteycDkV4IWBsO+PU48JonrPzV9ODjiI2XrjmA05KInLgF5ivZ/YGQ==",
+            "version": "9.1.0",
+            "resolved": "https://registry.npmjs.org/@types/mocha/-/mocha-9.1.0.tgz",
+            "integrity": "sha512-QCWHkbMv4Y5U9oW10Uxbr45qMMSzl4OzijsozynUAgx3kEHUdXB00udx2dWDQ7f2TU2a2uuiFaRZjCe3unPpeg==",
             "dev": true
         },
         "@types/node": {
diff --git a/package.json b/package.json
index 2f544be..f39f6be 100644
--- a/package.json
+++ b/package.json
@@ -241,7 +241,7 @@
     "lint": "tslint test/*.ts -t verbose"
   },
   "devDependencies": {
-    "@types/mocha": "^8.2.1",
+    "@types/mocha": "^9.1.0",
     "@types/node": "^14.14.31",
     "fitnesse-format": "^1.0.5",
     "fs": "0.0.1-security",