diff --git a/libtmux/session.py b/libtmux/session.py
index cd6af00..e4c02e2 100644
--- a/libtmux/session.py
+++ b/libtmux/session.py
@@ -263,7 +263,7 @@ class Session(TmuxMappingObject, TmuxRelationalObject, EnvironmentMixin):
             if isinstance(target_window, int):
                 target = '-t%s:%d' % (self.name, target_window)
             else:
-                target = '-t%s' % target_window
+                target = '-t%s:%s' % (self.name, target_window)
 
         proc = self.cmd('kill-window', target)
 
diff --git a/libtmux/window.py b/libtmux/window.py
index e62e8df..f452575 100644
--- a/libtmux/window.py
+++ b/libtmux/window.py
@@ -366,7 +366,7 @@ class Window(TmuxMappingObject, TmuxRelationalObject):
         if target_pane in ['-l', '-U', '-D', '-L', '-R']:
             proc = self.cmd('select-pane', '-t%s' % self.id, target_pane)
         else:
-            proc = self.cmd('select-pane', '-t%s' % target_pane)
+            proc = self.cmd('select-pane', '-t%%%s' % target_pane)
 
         if proc.stderr:
             raise exc.LibTmuxException(proc.stderr)