diff --git a/kms_key/README.md b/kms_key/README.md
index d125975..d9ef42d 100644
--- a/kms_key/README.md
+++ b/kms_key/README.md
@@ -86,6 +86,7 @@ No modules.
 | <a name="input_kms_key_id"></a> [kms\_key\_id](#input\_kms\_key\_id) | AWS KMS Key ID (one per bucket).  This is currently ignored (and deprecated). | `string` | `null` | no |
 | <a name="input_kms_policy_document"></a> [kms\_policy\_document](#input\_kms\_policy\_document) | AWS KMS Key Policy Document JSON, merged with admin policy document | `string` | `""` | no |
 | <a name="input_multi_region"></a> [multi\_region](#input\_multi\_region) | Flag to enable or disable the use of a multi-region KMS key (default=false) | `bool` | `false` | no |
+| <a name="input_override_prefixes"></a> [override\_prefixes](#input\_override\_prefixes) | Map of strings to override prefixes such as s3 and kms. Recommended ONLY for advanced useage (say, for inf* things) | `map(string)` | `{}` | no |
 | <a name="input_tags"></a> [tags](#input\_tags) | AWS Tags to apply to appropriate resources (S3, KMS).  Do not include safeguard tags here, use the data\_safeguard field for such things. | `map(string)` | `{}` | no |
 | <a name="input_use_kms_encryption"></a> [use\_kms\_encryption](#input\_use\_kms\_encryption) | Enable AWS:KMS encryption (default). If false, enables SSE-S3 (AES256), needed for some AWS services access | `bool` | `true` | no |
 
diff --git a/kms_key/locals.tf b/kms_key/locals.tf
new file mode 100644
index 0000000..2f3607f
--- /dev/null
+++ b/kms_key/locals.tf
@@ -0,0 +1,3 @@
+locals {
+  __prefixes = merge(local._prefixes, var.override_prefixes)
+}