diff --git a/src/buffer.hh b/src/buffer.hh
index cc09831b..5f171e75 100644
--- a/src/buffer.hh
+++ b/src/buffer.hh
@@ -178,8 +178,10 @@ public:
 
     const String& line_content(size_t l) const { return m_lines[l].content; }
 
-    OptionManager& option_manager() { return m_option_manager; }
-    HookManager&   hook_manager()   { return m_hook_manager; }
+    OptionManager&       option_manager()       { return m_option_manager; }
+    const OptionManager& option_manager() const { return m_option_manager; }
+    HookManager&         hook_manager()         { return m_hook_manager; }
+    const HookManager&   hook_manager()   const { return m_hook_manager; }
 
 private:
     friend class BufferIterator;
diff --git a/src/window.hh b/src/window.hh
index d36755fe..455830e5 100644
--- a/src/window.hh
+++ b/src/window.hh
@@ -36,8 +36,11 @@ public:
 
     HighlighterGroup& highlighters() { return m_highlighters; }
 
-    HookManager&   hook_manager()   { return m_hook_manager; }
-    OptionManager& option_manager() { return m_option_manager; }
+    OptionManager&       option_manager()       { return m_option_manager; }
+    const OptionManager& option_manager() const { return m_option_manager; }
+    HookManager&         hook_manager()         { return m_hook_manager; }
+    const HookManager&   hook_manager()   const { return m_hook_manager; }
+
 
 private:
     friend class Buffer;