diff --git a/modus-operandi-theme.el b/modus-operandi-theme.el
index 93dd89d..a8d189a 100644
--- a/modus-operandi-theme.el
+++ b/modus-operandi-theme.el
@@ -50,7 +50,9 @@
 
 
 
-(require 'modus-themes)
+(if (>= emacs-major-version 28)
+    (require-theme 'modus-themes)
+  (require 'modus-themes))
 
 (deftheme modus-operandi
   "Accessible and customizable light theme (WCAG AAA standard).
diff --git a/modus-vivendi-theme.el b/modus-vivendi-theme.el
index c605e2f..9dfa839 100644
--- a/modus-vivendi-theme.el
+++ b/modus-vivendi-theme.el
@@ -50,7 +50,9 @@
 
 
 
-(require 'modus-themes)
+(if (>= emacs-major-version 28)
+    (require-theme 'modus-themes)
+  (require 'modus-themes))
 
 (deftheme modus-vivendi
   "Accessible and customizable light theme (WCAG AAA standard).