diff --git a/CHANGELOG.md b/CHANGELOG.md
index a2a5903..ef27c77 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -47,6 +47,11 @@ system, you must also run the `--upgrade` command in each repository:
 
 - Prevent `cd` commands printing out excess details when `CDPATH` is set (#156)
 
+### Changed
+
+- Prevent global options set in `GREP_OPTIONS` enviroment variable from
+  breaking transcrypt's use of grep (#166)
+
 ## [2.2.3] - 2023-03-09
 
 ### Fixed
diff --git a/transcrypt b/transcrypt
index b6a3432..d917556 100755
--- a/transcrypt
+++ b/transcrypt
@@ -13,6 +13,11 @@ set -euo pipefail
 # that can be be found in the LICENSE file.
 #
 
+##### OVERRIDES
+
+# Disable any global grep options, to avoid problems like '--colors=always'
+GREP_OPTIONS=""
+
 ##### CONSTANTS
 
 # the release version of this script