diff --git a/src/stacosys/i18n/messages.py b/src/stacosys/i18n/messages.py
new file mode 100644
index 0000000..d64cbac
--- /dev/null
+++ b/src/stacosys/i18n/messages.py
@@ -0,0 +1,17 @@
+import configparser
+import os
+
+
+class Messages:
+    def __init__(self):
+        self.property_dict = {}
+
+    def load_messages(self, lang):
+        config = configparser.ConfigParser()
+        config.read(os.path.join(os.path.dirname(__file__), 'messages_' + lang + '.properties'))
+
+        for key, value in config.items('messages'):
+            self.property_dict[key] = value
+
+    def get(self, key):
+        return self.property_dict.get(key)
diff --git a/src/stacosys/i18n/messages_en.properties b/src/stacosys/i18n/messages_en.properties
new file mode 100644
index 0000000..85d02a7
--- /dev/null
+++ b/src/stacosys/i18n/messages_en.properties
@@ -0,0 +1,6 @@
+[messages]
+login.failure.username=Username or password incorrect
+logout.flash=You have been logged out.
+admin.comment.notfound=Comment not found.
+admin.comment.approved=Comment published.
+admin.comment.deleted=Comment deleted.
\ No newline at end of file
diff --git a/src/stacosys/i18n/messages_fr.properties b/src/stacosys/i18n/messages_fr.properties
new file mode 100644
index 0000000..9137863
--- /dev/null
+++ b/src/stacosys/i18n/messages_fr.properties
@@ -0,0 +1,6 @@
+[messages]
+login.failure.username=Identifiant ou mot de passe incorrect
+logout.flash=Vous avez été déconnecté.
+admin.comment.notfound=Commentaire introuvable
+admin.comment.approved=Commentaire publié
+admin.comment.deleted=Commentaire supprimé
\ No newline at end of file
diff --git a/src/stacosys/interface/web/admin.py b/src/stacosys/interface/web/admin.py
index 9e35d50..9b8c0ef 100644
--- a/src/stacosys/interface/web/admin.py
+++ b/src/stacosys/interface/web/admin.py
@@ -37,10 +37,7 @@ def login():
         if is_login_ok(username, password):
             session["user"] = username
             return redirect("/web/admin")
-        if app.config["CONFIG"].get(ConfigParameter.LANG) == "fr":
-            flash("Identifiant ou mot de passe incorrect")
-        else:
-            flash("Username or password incorrect")
+        flash(app.config["MESSAGES"].get("login.failure.username"))
         return redirect("/web/login")
     # GET
     return render_template(
@@ -51,10 +48,7 @@ def login():
 @app.route("/web/logout", methods=["GET"])
 def logout():
     session.pop("user")
-    if app.config["CONFIG"].get(ConfigParameter.LANG) == "fr":
-        flash("Vous avez été déconnecté.")
-    else:
-        flash("You have been logged out.")
+    flash(app.config["MESSAGES"].get("logout.flash"))
     return redirect("/web/admin")
 
 
@@ -78,21 +72,12 @@ def admin_homepage():
 def admin_action():
     comment = dao.find_comment_by_id(request.form.get("comment"))
     if comment is None:
-        if app.config["CONFIG"].get(ConfigParameter.LANG) == "fr":
-            flash("Commentaire introuvable")
-        else:
-            flash("Comment not found.")
+        flash(app.config["MESSAGES"].get("admin.comment.notfound"))
     elif request.form.get("action") == "APPROVE":
         dao.publish_comment(comment)
         app.config["RSS"].generate()
-        if app.config["CONFIG"].get(ConfigParameter.LANG) == "fr":
-            flash("Commentaire publié")
-        else:
-            flash("Comment published.")
+        flash(app.config["MESSAGES"].get("admin.comment.approved"))
     else:
         dao.delete_comment(comment)
-        if app.config["CONFIG"].get(ConfigParameter.LANG) == "fr":
-            flash("Commentaire supprimé")
-        else:
-            flash("Comment deleted.")
+        flash(app.config["MESSAGES"].get("admin.comment.deleted"))
     return redirect("/web/admin")
diff --git a/src/stacosys/run.py b/src/stacosys/run.py
index 5634764..255c424 100644
--- a/src/stacosys/run.py
+++ b/src/stacosys/run.py
@@ -7,6 +7,7 @@ import os
 import sys
 
 from stacosys.db import database
+from stacosys.i18n.messages import Messages
 from stacosys.interface import api, app, form
 from stacosys.interface.web import admin
 from stacosys.service.configuration import Config, ConfigParameter
@@ -64,6 +65,12 @@ def configure_rss(config):
     return rss
 
 
+def configure_localization(config):
+    messages = Messages()
+    messages.load_messages(config.get(ConfigParameter.LANG))
+    return messages
+
+
 def main(config_pathname):
     logger = configure_logging()
     config = load_and_validate_config(config_pathname, logger)
@@ -72,11 +79,13 @@ def main(config_pathname):
     logger.info("Start Stacosys application")
     rss = configure_rss(config)
     mailer = configure_and_validate_mailer(config, logger)
+    messages = configure_localization(config)
 
     logger.info("start interfaces %s %s %s", api, form, admin)
     app.config["CONFIG"] = config
     app.config["MAILER"] = mailer
     app.config["RSS"] = rss
+    app.config["MESSAGES"] = messages
     app.run(
         host=config.get(ConfigParameter.HTTP_HOST),
         port=config.get_int(ConfigParameter.HTTP_PORT),