diff --git a/libraries/Ticker/Ticker.cpp b/libraries/Ticker/Ticker.cpp
index a5e750a60..b348798c6 100644
--- a/libraries/Ticker/Ticker.cpp
+++ b/libraries/Ticker/Ticker.cpp
@@ -29,6 +29,9 @@ extern "C" {
 #include "osapi.h"
 }
 
+const int ONCE   = 0;
+const int REPEAT = 1;
+
 #include "Ticker.h"
 
 Ticker::Ticker()
@@ -41,10 +44,8 @@ Ticker::~Ticker()
 	detach();
 }
 
-void Ticker::_attach_ms(callback_with_arg_t callback, uint32_t milliseconds, void* arg)
+void Ticker::_attach_ms(uint32_t milliseconds, bool repeat, callback_with_arg_t callback, uint32_t arg)
 {
-	const int REPEAT = 1;
-
 	if (_timer)
 	{
 		os_timer_disarm(_timer);
@@ -54,8 +55,8 @@ void Ticker::_attach_ms(callback_with_arg_t callback, uint32_t milliseconds, voi
 		_timer = new ETSTimer;
 	}
 
-	os_timer_setfn(_timer, reinterpret_cast<ETSTimerFunc*>(callback), arg);
-	os_timer_arm(_timer, milliseconds, REPEAT);
+	os_timer_setfn(_timer, reinterpret_cast<ETSTimerFunc*>(callback), reinterpret_cast<void*>(arg));
+	os_timer_arm(_timer, milliseconds, (repeat)?REPEAT:ONCE);
 }
 
 void Ticker::detach()
diff --git a/libraries/Ticker/Ticker.h b/libraries/Ticker/Ticker.h
index c107532ed..ea3f59f1c 100644
--- a/libraries/Ticker/Ticker.h
+++ b/libraries/Ticker/Ticker.h
@@ -37,36 +37,65 @@ public:
 	typedef void (*callback_t)(void);
 	typedef void (*callback_with_arg_t)(void*);
 
-	void attach(callback_t callback, float seconds)
+	void attach(float seconds, callback_t callback)
 	{
-		_attach_ms(reinterpret_cast<callback_with_arg_t>(callback), seconds * 1000, 0);
+		_attach_ms(seconds * 1000, true, reinterpret_cast<callback_with_arg_t>(callback), 0);
 	}
 
-	void attach_ms(callback_t callback, uint32_t milliseconds)
+	void attach_ms(uint32_t milliseconds, callback_t callback)
 	{
-		_attach_ms(reinterpret_cast<callback_with_arg_t>(callback), milliseconds, 0);
+		_attach_ms(milliseconds, true, reinterpret_cast<callback_with_arg_t>(callback), 0);
 	}
 
 	template<typename TArg>
-	void attach(void (*callback)(TArg), float seconds, TArg arg)
+	void attach(float seconds, void (*callback)(TArg), TArg arg)
 	{
 		static_assert(sizeof(TArg) <= sizeof(uint32_t), "attach() callback argument size must be <= 4 bytes");
-		uint32_t arg32 = static_cast<uint32_t>(arg);
-		_attach_ms(reinterpret_cast<callback_with_arg_t>(callback), seconds * 1000, reinterpret_cast<void*>(arg32));
+		// C-cast serves two purposes:
+		// static_cast for smaller integer types,
+		// reinterpret_cast + const_cast for pointer types
+		uint32_t arg32 = (uint32_t)arg;
+		_attach_ms(seconds * 1000, true, reinterpret_cast<callback_with_arg_t>(callback), arg32);
 	}
 
 	template<typename TArg>
-	void attach_ms(void (*callback)(TArg), uint32_t milliseconds, TArg arg)
+	void attach_ms(uint32_t milliseconds, void (*callback)(TArg), TArg arg)
 	{
 		static_assert(sizeof(TArg) <= sizeof(uint32_t), "attach_ms() callback argument size must be <= 4 bytes");
-		uint32_t arg32 = static_cast<uint32_t>(arg);
-		_attach_ms(reinterpret_cast<callback_with_arg_t>(callback), milliseconds, reinterpret_cast<void*>(arg32));
+		uint32_t arg32 = (uint32_t)arg;
+		_attach_ms(milliseconds, true, reinterpret_cast<callback_with_arg_t>(callback), arg32);
+	}
+
+	void once(float seconds, callback_t callback)
+	{
+		_attach_ms(seconds * 1000, false, reinterpret_cast<callback_with_arg_t>(callback), 0);
+	}
+
+	void once_ms(uint32_t milliseconds, callback_t callback)
+	{
+		_attach_ms(milliseconds, false, reinterpret_cast<callback_with_arg_t>(callback), 0);	
+	}
+
+	template<typename TArg>
+	void once(float seconds, void (*callback)(TArg), TArg arg)
+	{
+		static_assert(sizeof(TArg) <= sizeof(uint32_t), "attach() callback argument size must be <= 4 bytes");
+		uint32_t arg32 = (uint32_t)(arg);
+		_attach_ms(seconds * 1000, false, reinterpret_cast<callback_with_arg_t>(callback), arg32);
+	}
+
+	template<typename TArg>
+	void once_ms(uint32_t milliseconds, void (*callback)(TArg), TArg arg)
+	{
+		static_assert(sizeof(TArg) <= sizeof(uint32_t), "attach_ms() callback argument size must be <= 4 bytes");
+		uint32_t arg32 = (uint32_t)(arg);
+		_attach_ms(milliseconds, false, reinterpret_cast<callback_with_arg_t>(callback), arg32);
 	}
 
 	void detach();
 
 protected:	
-	void _attach_ms(callback_with_arg_t callback, uint32_t milliseconds, void* arg);
+	void _attach_ms(uint32_t milliseconds, bool repeat, callback_with_arg_t callback, uint32_t arg);
 
 
 protected:
diff --git a/libraries/Ticker/examples/TickerBasic/TickerBasic.ino b/libraries/Ticker/examples/TickerBasic/TickerBasic.ino
index 4b21818e5..772b5b74c 100644
--- a/libraries/Ticker/examples/TickerBasic/TickerBasic.ino
+++ b/libraries/Ticker/examples/TickerBasic/TickerBasic.ino
@@ -28,7 +28,7 @@ void flip()
   // when the counter reaches a certain value, start blinking like crazy
   if (count == 20)
   {
-    flipper.attach(&flip, 0.1);
+    flipper.attach(0.1, flip);
   }
   // when the counter reaches yet another value, stop blinking
   else if (count == 120)
@@ -42,7 +42,7 @@ void setup() {
   digitalWrite(1, LOW);
   
   // flip the pin every 0.3s
-  flipper.attach(&flip, 0.3);
+  flipper.attach(0.3, flip);
 }
 
 void loop() {
diff --git a/libraries/Ticker/examples/TickerParameter/TickerParameter.ino b/libraries/Ticker/examples/TickerParameter/TickerParameter.ino
index 832f35405..80eec5e67 100644
--- a/libraries/Ticker/examples/TickerParameter/TickerParameter.ino
+++ b/libraries/Ticker/examples/TickerParameter/TickerParameter.ino
@@ -25,11 +25,11 @@ void setup() {
   pinMode(1, OUTPUT);
   digitalWrite(1, LOW);
   
-  // call setPin(0) every 25 ms
-  tickerSetLow.attach_ms(&setPin, 25, 0);
+  // every 25 ms, call setPin(0) 
+  tickerSetLow.attach_ms(25, setPin, 0);
   
-  // call setPin(1) every 26 ms
-  tickerSetHigh.attach_ms(&setPin, 26, 1);
+  // every 26 ms, call setPin(1)
+  tickerSetHigh.attach_ms(26, setPin, 1);
 }
 
 void loop() {
diff --git a/libraries/Ticker/keywords.txt b/libraries/Ticker/keywords.txt
index 8fae1c33e..89cca9a0c 100644
--- a/libraries/Ticker/keywords.txt
+++ b/libraries/Ticker/keywords.txt
@@ -12,6 +12,8 @@
 
 attach	KEYWORD2
 attach_ms	KEYWORD2
+once	KEYWORD2
+once_ms	KEYWORD2
 detach	KEYWORD2
 
 #######################################