diff --git a/Timer.st b/Timer.st
index 438d2de..a5d3e93 100644
--- a/Timer.st
+++ b/Timer.st
@@ -56,7 +56,13 @@ Object subclass: Timer [
 
     cancel [
         <category: 'management'>
-        schedule removeTimer: self.
+        "Remember that the timer is gone."
+        schedule := nil.
+    ]
+
+    isCanceled [
+        <category: 'management'>
+        ^ schedule == nil.
     ]
 ]
 
@@ -111,13 +117,6 @@ bit difficult to do this race free.'>
         ^ sched
     ]
 
-    removeTimer: aSched [
-        <category: 'schedule'>
-        sem critical: [
-            queue remove: aSched ifAbsent: [].
-        ].
-    ]
-
     runTimers [
         <category: 'delay_loop'>
 
@@ -131,24 +130,20 @@ bit difficult to do this race free.'>
 
     fireTimers: now [
         <category: 'private'>
-        | copy |
-
-        "Create a shallow copy of the data"
-        copy := sem critical: [queue copy].
 
         "Now execute the timers. One way or another this is crazy. If we have
         a long blocking application or a deadlock the timer queue will get
         stuck. But if we run this in a new process a later process might be run
         before this process, changing the order of the timers."
-        copy do: [:each |
-            each timeout > now ifTrue: [^true].
-            sem critical: [queue remove: each].
-            [
-                each fire
-            ] on: Error do: [:e |
+        "Only this process will remove items, this is why we can check isEmpty
+        without having the lock"
+        [queue isEmpty or: [queue first timeout > now]] whileFalse: [ | each |
+            each := sem critical: [queue removeFirst].
+            each isCanceled ifFalse: [
+                [each fire] on: Error do: [:e |
                 e logException: 'Execution of timer failed: %1' % {e tag} area: #timer.
-            ].
-        ].
+            ]].
+        ]
     ]
 ]