diff --git a/news/handler/news.go b/news/handler/news.go
index 57b8ad8..316c368 100644
--- a/news/handler/news.go
+++ b/news/handler/news.go
@@ -79,6 +79,17 @@ func (n *News) Headlines(ctx context.Context, req *pb.HeadlinesRequest, rsp *pb.
 		date = req.Date
 	}
 
+	var seen bool
+	for _, locale := range Locales {
+		if locale == req.Locale {
+			seen = true
+			break
+		}
+	}
+	if !seen {
+		return errors.BadRequest("news.headlines", "invalid locale")
+	}
+
 	vals := url.Values{}
 	vals.Set("api_token", n.apiKey)
 	vals.Set("locale", locale)
diff --git a/news/handler/types.go b/news/handler/types.go
new file mode 100644
index 0000000..200b340
--- /dev/null
+++ b/news/handler/types.go
@@ -0,0 +1,61 @@
+package handler
+
+var (
+	Locales = []string{
+                "ar",
+                "am",
+                "au",
+                "at",
+                "by",
+                "be",
+                "bo",
+                "br",
+                "bg",
+                "ca",
+                "cl",
+                "cn",
+                "co",
+                "hr",
+                "cz",
+                "ec",
+                "eg",
+                "fr",
+                "de",
+                "gr",
+                "hn",
+                "hk",
+                "in",
+                "id",
+                "ir",
+                "ie",
+                "il",
+                "it",
+                "jp",
+                "kr",
+                "mx",
+                "nl",
+                "nz",
+                "ni",
+                "pk",
+                "pa",
+                "pe",
+                "pl",
+                "pt",
+                "qa",
+                "ro",
+                "ru",
+                "sa",
+                "za",
+                "es",
+                "ch",
+                "sy",
+                "tw",
+                "th",
+                "tr",
+                "ua",
+                "gb",
+                "us",
+                "uy",
+                "ve",
+	}
+)