diff --git a/Documentation/NuttxPortingGuide.html b/Documentation/NuttxPortingGuide.html
index 1ce105c8f8..93c629fe51 100644
--- a/Documentation/NuttxPortingGuide.html
+++ b/Documentation/NuttxPortingGuide.html
@@ -2148,7 +2148,7 @@ extern void up_ledoff(int led);
   </li>
   <li>
     <code>CONFIG_SCHED_WORKPERIOD</code>: How often the worker thread checks for
-    work.  Default: 50 MS.
+    work in units of microseconds.  Default: 50*1000 (50 MS).
   </li>
   <li>
     <code>CONFIG_SCHED_WORKSTACKSIZE</code>: The stack size allocated for the worker
diff --git a/configs/README.txt b/configs/README.txt
index 6ccd836642..17c29286e4 100644
--- a/configs/README.txt
+++ b/configs/README.txt
@@ -256,7 +256,7 @@ defconfig -- This is a configuration file similar to the Linux
 		CONFIG_SCHED_WORKPRIORITY - The execution priority of the worker
 		  thread.  Default: 50
 		CONFIG_SCHED_WORKPERIOD - How often the worker thread checks for
-		  work.  Default: 50 MS.
+		  work in units of microseconds.  Default: 50*1000 (50 MS).
 		CONFIG_SCHED_WORKSTACKSIZE - The stack size allocated for the worker
 		  thread.  Default: CONFIG_IDLETHREAD_STACKSIZE.
 		CONFIG_SIG_SIGWORK - The signal number that will be used to wake-up
diff --git a/configs/stm3210e-eval/RIDE/defconfig b/configs/stm3210e-eval/RIDE/defconfig
index 7e9a52b642..cc08dc9c01 100755
--- a/configs/stm3210e-eval/RIDE/defconfig
+++ b/configs/stm3210e-eval/RIDE/defconfig
@@ -307,7 +307,7 @@ CONFIG_HAVE_LIBM=n
 # CONFIG_SCHED_WORKPRIORITY - The execution priority of the worker
 #  thread.  Default: 50
 # CONFIG_SCHED_WORKPERIOD - How often the worker thread checks for
-#  work.  Default: 50 MS.
+#  work in units of microseconds.  Default: 50*1000 (50 MS).
 # CONFIG_SCHED_WORKSTACKSIZE - The stack size allocated for the worker
 #  thread.  Default: CONFIG_IDLETHREAD_STACKSIZE.
 # CONFIG_SIG_SIGWORK - The signal number that will be used to wake-up
@@ -340,7 +340,7 @@ CONFIG_SDCLONE_DISABLE=y
 CONFIG_NXFLAT=n
 CONFIG_SCHED_WORKQUEUE=n
 CONFIG_SCHED_WORKPRIORITY=50
-CONFIG_SCHED_WORKPERIOD=50
+CONFIG_SCHED_WORKPERIOD=(50*1000)
 CONFIG_SCHED_WORKSTACKSIZE=1024
 CONFIG_SIG_SIGWORK=4
 
diff --git a/configs/stm3210e-eval/nsh/defconfig b/configs/stm3210e-eval/nsh/defconfig
index 19f682d908..5a41b5b1ee 100755
--- a/configs/stm3210e-eval/nsh/defconfig
+++ b/configs/stm3210e-eval/nsh/defconfig
@@ -317,7 +317,7 @@ CONFIG_HAVE_LIBM=n
 # CONFIG_SCHED_WORKPRIORITY - The execution priority of the worker
 #  thread.  Default: 50
 # CONFIG_SCHED_WORKPERIOD - How often the worker thread checks for
-#  work.  Default: 50 MS.
+#  work in units of microseconds.  Default: 50*1000 (50 MS).
 # CONFIG_SCHED_WORKSTACKSIZE - The stack size allocated for the worker
 #  thread.  Default: CONFIG_IDLETHREAD_STACKSIZE.
 # CONFIG_SIG_SIGWORK - The signal number that will be used to wake-up
@@ -349,7 +349,7 @@ CONFIG_SDCLONE_DISABLE=y
 CONFIG_NXFLAT=n
 CONFIG_SCHED_WORKQUEUE=y
 CONFIG_SCHED_WORKPRIORITY=50
-CONFIG_SCHED_WORKPERIOD=50
+CONFIG_SCHED_WORKPERIOD=(50*1000)
 CONFIG_SCHED_WORKSTACKSIZE=1024
 CONFIG_SIG_SIGWORK=4
 
diff --git a/configs/stm3210e-eval/ostest/defconfig b/configs/stm3210e-eval/ostest/defconfig
index 45e416804a..0ea76f6cdf 100755
--- a/configs/stm3210e-eval/ostest/defconfig
+++ b/configs/stm3210e-eval/ostest/defconfig
@@ -319,7 +319,7 @@ CONFIG_HAVE_LIBM=n
 # CONFIG_SCHED_WORKPRIORITY - The execution priority of the worker
 #  thread.  Default: 50
 # CONFIG_SCHED_WORKPERIOD - How often the worker thread checks for
-#  work.  Default: 50 MS.
+#  work in units of microseconds.  Default: 50*1000 (50 MS).
 # CONFIG_SCHED_WORKSTACKSIZE - The stack size allocated for the worker
 #  thread.  Default: CONFIG_IDLETHREAD_STACKSIZE.
 # CONFIG_SIG_SIGWORK - The signal number that will be used to wake-up
@@ -351,7 +351,7 @@ CONFIG_SDCLONE_DISABLE=y
 CONFIG_NXFLAT=n
 CONFIG_SCHED_WORKQUEUE=n
 CONFIG_SCHED_WORKPRIORITY=50
-CONFIG_SCHED_WORKPERIOD=50
+CONFIG_SCHED_WORKPERIOD=(50*1000)
 CONFIG_SCHED_WORKSTACKSIZE=1024
 CONFIG_SIG_SIGWORK=4
 
diff --git a/configs/stm3210e-eval/usbserial/defconfig b/configs/stm3210e-eval/usbserial/defconfig
index 6d7adf0c04..23910eb2d3 100755
--- a/configs/stm3210e-eval/usbserial/defconfig
+++ b/configs/stm3210e-eval/usbserial/defconfig
@@ -319,7 +319,7 @@ CONFIG_HAVE_LIBM=n
 # CONFIG_SCHED_WORKPRIORITY - The execution priority of the worker
 #  thread.  Default: 50
 # CONFIG_SCHED_WORKPERIOD - How often the worker thread checks for
-#  work.  Default: 50 MS.
+#  work in units of microseconds.  Default: 50*1000 (50 MS).
 # CONFIG_SCHED_WORKSTACKSIZE - The stack size allocated for the worker
 #  thread.  Default: CONFIG_IDLETHREAD_STACKSIZE.
 # CONFIG_SIG_SIGWORK - The signal number that will be used to wake-up
@@ -352,7 +352,7 @@ CONFIG_SDCLONE_DISABLE=y
 CONFIG_NXFLAT=n
 CONFIG_SCHED_WORKQUEUE=n
 CONFIG_SCHED_WORKPRIORITY=50
-CONFIG_SCHED_WORKPERIOD=50
+CONFIG_SCHED_WORKPERIOD=(50*1000)
 CONFIG_SCHED_WORKSTACKSIZE=1024
 CONFIG_SIG_SIGWORK=4
 
diff --git a/sched/work_thread.c b/sched/work_thread.c
index d1f415d777..1a772b6186 100755
--- a/sched/work_thread.c
+++ b/sched/work_thread.c
@@ -103,17 +103,24 @@ int work_thread(int argc, char *argv[])
   volatile FAR struct work_s *work;
   worker_t  worker;
   FAR void *arg;
+  uint32 elapsed;
+  uint32 remaining;
+  uint32 next;
+  int usec;
   irqstate_t flags;
 
   /* Loop forever */
 
+  usec = CONFIG_SCHED_WORKPERIOD;
+  flags = irqsave();
   for (;;)
     {
       /* Wait awhile to check the work list.  We will wait here until either
        * the time elapses or until we are awakened by a signal.
        */
 
-      usleep(CONFIG_SCHED_WORKPERIOD);
+      usleep(usec);
+      irqrestore(flags);
 
       /* First, perform garbage collection.  This cleans-up memory de-allocations
        * that were queued because they could not be freed in that execution
@@ -128,15 +135,19 @@ int work_thread(int argc, char *argv[])
        * we process items in the work list.
        */
 
+      next  = CONFIG_SCHED_WORKPERIOD / USEC_PER_TICK;
       flags = irqsave();
       work  = (FAR struct work_s *)g_work.head;
       while (work)
         {
           /* Is this work ready?  It is ready if there is no delay or if
-           * the delay has elapsed.
+           * the delay has elapsed. qtime is the time that the work was added
+           * to the work queue.  It will always be greater than or equal to
+           * zero.  Therefore a delay of zero will always execute immediately.
            */
 
-          if (work->delay == 0 || g_system_timer - work->qtime > work->delay)
+          elapsed = g_system_timer - work->qtime;
+          if (elapsed >= work->delay)
             {
               /* Remove the ready-to-execute work from the list */
 
@@ -166,12 +177,27 @@ int work_thread(int argc, char *argv[])
             }
           else
             {
-              /* This one is not ready, try the next in the list. */
+              /* This one is not ready.. will it be ready before the next
+               * scheduled wakeup interval?
+               */
+
+              remaining = elapsed - work->delay;
+              if (remaining < next)
+                {
+                  /* Yes.. Then schedule to wake up when the work is ready */
+
+                  next = remaining;
+                }
+              
+              /* Then try the next in the list. */
 
               work = (FAR struct work_s *)work->dq.flink;
             }
         }
-      irqrestore(flags);
+
+      /* Now calculate the microsecond delay we should wait */
+
+      usec = next * USEC_PER_TICK;
     }
 
   return OK; /* To keep some compilers happy */