diff --git a/lib/awful/titlebar.lua b/lib/awful/titlebar.lua
index 9197f032c..aedd9aef6 100644
--- a/lib/awful/titlebar.lua
+++ b/lib/awful/titlebar.lua
@@ -248,11 +248,8 @@ function titlebar.widget.button(c, name, selector, action)
 
     -- We do magic based on whether a client is focused above, so we need to
     -- connect to the corresponding signal here.
-    local function focus_func(o)
-        if o == c then update() end
-    end
-    capi.client.connect_signal("focus", focus_func)
-    capi.client.connect_signal("unfocus", focus_func)
+    c:connect_signal("focus", update)
+    c:connect_signal("unfocus", update)
 
     return ret
 end
@@ -309,6 +306,10 @@ function titlebar.widget.stickybutton(c)
     return widget
 end
 
+client.connect_signal("unmanage", function(c)
+    all_titlebars[c] = nil
+end)
+
 return setmetatable(titlebar, { __call = function(_, ...) return new(...) end})
 
 -- vim: filetype=lua:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80
diff --git a/lib/awful/widget/tasklist.lua b/lib/awful/widget/tasklist.lua
index a0605834f..ccae7fa16 100644
--- a/lib/awful/widget/tasklist.lua
+++ b/lib/awful/widget/tasklist.lua
@@ -181,6 +181,9 @@ function tasklist.new(screen, filter, buttons, style, update_function, base_widg
             queued_update = true
         end
     end
+    function w._unmanage(c)
+        data[c] = nil
+    end
     if instances == nil then
         instances = {}
         local function us(s)
@@ -219,7 +222,14 @@ function tasklist.new(screen, filter, buttons, style, update_function, base_widg
         capi.client.connect_signal("property::hidden", u)
         capi.client.connect_signal("tagged", u)
         capi.client.connect_signal("untagged", u)
-        capi.client.connect_signal("unmanage", u)
+        capi.client.connect_signal("unmanage", function(c)
+            u(c)
+            for s, i in pairs(instances) do
+                for _, tlist in pairs(i) do
+                    tlist._unmanage(c)
+                end
+            end
+        end)
         capi.client.connect_signal("list", u)
         capi.client.connect_signal("focus", u)
         capi.client.connect_signal("unfocus", u)
diff --git a/tests/test-leak-client.lua b/tests/test-leak-client.lua
new file mode 100644
index 000000000..205e48248
--- /dev/null
+++ b/tests/test-leak-client.lua
@@ -0,0 +1,78 @@
+-- Some memory leak checks involving clients as integration tests.
+local awful = require("awful")
+local wibox = require("wibox")
+
+-- "Enable" titlebars (so that the titlebar can prevent garbage collection)
+client.connect_signal("manage", function (c)
+    local buttons = awful.util.table.join(
+            awful.button({ }, 1, function()
+                client.focus = c
+                c:raise()
+                awful.mouse.client.move(c)
+            end),
+            awful.button({ }, 3, function()
+                client.focus = c
+                c:raise()
+                awful.mouse.client.resize(c)
+            end)
+            )
+
+    -- Widgets that are aligned to the left
+    local left_layout = wibox.layout.fixed.horizontal(awful.titlebar.widget.iconwidget(c))
+    left_layout:buttons(buttons)
+
+    -- The title goes in the middle
+    local title = awful.titlebar.widget.titlewidget(c)
+    title:set_align("center")
+    local middle_layout = wibox.layout.flex.horizontal(title)
+    middle_layout:buttons(buttons)
+
+    awful.titlebar(c):set_widget(wibox.layout.align.horizontal(
+        left_layout,
+        middle_layout,
+        wibox.layout.fixed.horizontal(
+            awful.titlebar.widget.floatingbutton(c),
+            awful.titlebar.widget.maximizedbutton(c),
+            awful.titlebar.widget.stickybutton(c),
+            awful.titlebar.widget.ontopbutton(c),
+            awful.titlebar.widget.closebutton(c)
+        )), { position = "bottom"})
+end)
+
+-- We tell the garbage collector when to work, disable it
+collectgarbage("stop")
+
+-- We try to get a client representing an already-closed client.
+-- The first iteration starts xterm, the second keeps a weak reference to it and
+-- closes it and the last one checks that the client object is GC'able.
+local objs = nil
+local steps = {
+    function(count)
+        if count == 1 then
+            awful.spawn("xterm")
+        elseif not objs then
+            local c = client.get()[1]
+            if c then
+                objs = setmetatable({ c }, { __mode = "v" })
+                c:kill()
+            end
+        else
+            assert(#objs == 1)
+
+            -- Test that we have a client and that it's invalid (tostring()
+            -- causes an "invalid object" error)
+            local success, msg = pcall(function() tostring(objs[1]) end)
+            assert(not success)
+            assert(msg:find("invalid object"), msg)
+
+            -- Check that it is garbage-collectable
+            collectgarbage("collect")
+            assert(#objs == 0)
+            return true
+        end
+    end,
+}
+
+require("_runner").run_steps(steps)
+
+-- vim: filetype=lua:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80