diff --git a/justfile b/justfile
index 2cf1afc..9c3a53a 100644
--- a/justfile
+++ b/justfile
@@ -49,6 +49,7 @@ just_boolean_settings := """
   allow-duplicate-recipes
   allow-duplicate-variables
   dotenv-load
+  dotenv-required
   export
   fallback
   ignore-comments
diff --git a/syntax/just.vim b/syntax/just.vim
index a18c0e6..4e8a2ae 100644
--- a/syntax/just.vim
+++ b/syntax/just.vim
@@ -154,10 +154,10 @@ syn match justAssignment "\v^\h\k*%(\s|\\\n)*:\=" transparent contains=justAssig
 
 syn match justSet '\v^set' contained
 syn keyword justSetKeywords
-   \ allow-duplicate-recipes allow-duplicate-variables dotenv-load dotenv-filename dotenv-path export fallback ignore-comments positional-arguments quiet shell tempdir windows-shell
+   \ allow-duplicate-recipes allow-duplicate-variables dotenv-load dotenv-filename dotenv-path dotenv-required export fallback ignore-comments positional-arguments quiet shell tempdir windows-shell
    \ contained
 syn keyword justSetDeprecatedKeywords windows-powershell contained
-syn match justBooleanSet "\v^set%(\s|\\\n)+%(allow-duplicate-%(recip|variabl)es|dotenv-load|export|fallback|ignore-comments|positional-arguments|quiet|windows-powershell)%(%(\s|\\\n)*:\=%(\s|\\\n)*%(true|false))?$"
+syn match justBooleanSet "\v^set%(\s|\\\n)+%(allow-duplicate-%(recip|variabl)es|dotenv-%(loa|require)d|export|fallback|ignore-comments|positional-arguments|quiet|windows-powershell)%(%(\s|\\\n)*:\=%(\s|\\\n)*%(true|false))?$"
    \ contains=justSet,justSetKeywords,justSetDeprecatedKeywords,justAssignmentOperator,justBoolean
    \ transparent
 
diff --git a/tests/cases/set.html b/tests/cases/set.html
index 463bdc2..f2afa91 100644
--- a/tests/cases/set.html
+++ b/tests/cases/set.html
@@ -51,3 +51,7 @@
 
 <span class="Statement">set</span> <span class="Keyword">dotenv-filename</span> <span class="Operator">:=</span> <span class="String">"mydotenv"</span>
 <span class="Statement">set</span> <span class="Keyword">dotenv-path</span> <span class="Operator">:=</span> <span class="String">'/tmp/dotenv'</span>
+
+<span class="Statement">set</span> <span class="Keyword">dotenv-required</span>
+<span class="Statement">set</span> <span class="Keyword">dotenv-required</span> <span class="Operator">:=</span> <span class="Boolean">true</span>
+<span class="Statement">set</span> <span class="Keyword">dotenv-required</span> <span class="Operator">:=</span> <span class="Boolean">false</span>
diff --git a/tests/cases/set.just b/tests/cases/set.just
index 6260c19..e5a9132 100644
--- a/tests/cases/set.just
+++ b/tests/cases/set.just
@@ -51,3 +51,7 @@ set tempdir := x'${XDG_CACHE_HOME:-/tmp}'
 
 set dotenv-filename := "mydotenv"
 set dotenv-path := '/tmp/dotenv'
+
+set dotenv-required
+set dotenv-required := true
+set dotenv-required := false