diff --git a/src/astrognome.c b/src/astrognome.c
index a468f8f..e3ad27a 100644
--- a/src/astrognome.c
+++ b/src/astrognome.c
@@ -16,6 +16,8 @@ GtkBuilder *builder;
 static gboolean option_version,
                 option_quit,
                 option_new_window;
+GtkFileFilter *filter_all = NULL,
+              *filter_chart = NULL;
 
 const char *moonStateName[] = {
     "New Moon",
@@ -50,6 +52,20 @@ application_activate_cb(AgApp *app, gpointer user_data)
     run_action(app, FALSE);
 }
 
+void
+init_filters(void)
+{
+    filter_all = gtk_file_filter_new();
+    gtk_file_filter_set_name(filter_all, _("All files"));
+    gtk_file_filter_add_pattern(filter_all, "*");
+    g_object_ref_sink(filter_all);
+
+    filter_chart = gtk_file_filter_new();
+    gtk_file_filter_set_name(filter_chart, _("Astrognome charts"));
+    gtk_file_filter_add_pattern(filter_chart, "*.agc");
+    g_object_ref_sink(filter_chart);
+}
+
 int
 main(int argc, char *argv[])
 {
@@ -88,6 +104,8 @@ main(int argc, char *argv[])
         return EXIT_SUCCESS;
     }
 
+    init_filters();
+
     app = ag_app_new();
     g_signal_connect(app, "activate", G_CALLBACK(application_activate_cb), NULL);
     g_application_set_default(G_APPLICATION(app));
diff --git a/src/astrognome.h b/src/astrognome.h
new file mode 100644
index 0000000..f935f30
--- /dev/null
+++ b/src/astrognome.h
@@ -0,0 +1,8 @@
+#ifndef __ASTROGNOME_H__
+#define __ASTROGNOME_H__
+
+extern GtkFileFilter *filter_all,
+                     *filter_chart;
+
+#endif /* __ASTROGNOME_H__ */
+