diff --git a/pixelocr/document.py b/pixelocr/document.py
index bc4eff3..f64ac27 100644
--- a/pixelocr/document.py
+++ b/pixelocr/document.py
@@ -15,6 +15,7 @@
 
 
 import itertools
+import subprocess
 from glob import glob
 from os import path
 
@@ -23,6 +24,7 @@ from .image import Image
 from .page import Page, Space
 from .glyphdb import GlyphDB, Style, SPACE, NEWLINE
 from .config import Configuration
+from .utils import cached_property
 
 
 class Document(object):
@@ -71,8 +73,18 @@ class Document(object):
         try:
             glyph_data = self.glyphdb[glyph]
         except KeyError:
+            self.switch_layout(glyph.word.guess_language())
             text, bold, italic = self.ui.ask_for_help(glyph, glyph.word.guess_bold(), glyph.word.guess_italic())
             glyph_data = self.glyphdb.add_glyph(glyph, text, bold, italic)
         self.last_style = glyph_data.style
         return glyph_data
 
+    @cached_property
+    def language_map(self):
+        languages = self.config.get('languages', {})
+        return {letter: lang_name for lang_name, opts in languages.items() for letter in opts.get('alphabet', ())}
+
+    def switch_layout(self, language):
+        cmd = self.config.get('languages', {}).get(language, {}).get('command')
+        if cmd:
+            return subprocess.call(cmd, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
diff --git a/pixelocr/page.py b/pixelocr/page.py
index 7bbf0c8..cd19a5a 100644
--- a/pixelocr/page.py
+++ b/pixelocr/page.py
@@ -269,6 +269,17 @@ class Word(PageObject):
         image = line.image[:, beginning.left:end.right]
         super().__init__(line.document, image)
 
+    def guess_language(self):
+        counts = defaultdict(int)
+        language_map = self.document.language_map
+        known_glyph_info = self._known_glyph_info()
+        if not known_glyph_info:
+            return None
+        for glyph_info in known_glyph_info:
+            counts[language_map.get(glyph_info.text)] += 1
+        language, count = sorted(counts.items(), reverse=True)[0]
+        return language
+
     def guess_bold(self):
         return self._guess('bold')