diff --git a/src/Key.h b/src/Key.h
index 0977fa0..be6c70a 100644
--- a/src/Key.h
+++ b/src/Key.h
@@ -34,8 +34,8 @@
 
 #include <Arduino.h>
 
-#define OPEN LOW
-#define CLOSED HIGH
+#define KEYPAD_OPEN LOW
+#define KEYPAD_CLOSED HIGH
 
 typedef unsigned int uint;
 typedef enum{ IDLE, PRESSED, HOLD, RELEASED } KeyState;
diff --git a/src/Keypad.cpp b/src/Keypad.cpp
index f146a6d..86d244d 100644
--- a/src/Keypad.cpp
+++ b/src/Keypad.cpp
@@ -154,18 +154,18 @@ void Keypad::nextKeyState(byte idx, boolean button) {
 
 	switch (key[idx].kstate) {
 		case IDLE:
-			if (button==CLOSED) {
+			if (button==KEYPAD_CLOSED) {
 				transitionTo (idx, PRESSED);
 				holdTimer = millis(); }		// Get ready for next HOLD state.
 			break;
 		case PRESSED:
 			if ((millis()-holdTimer)>holdTime)	// Waiting for a key HOLD...
 				transitionTo (idx, HOLD);
-			else if (button==OPEN)				// or for a key to be RELEASED.
+			else if (button==KEYPAD_OPEN)				// or for a key to be RELEASED.
 				transitionTo (idx, RELEASED);
 			break;
 		case HOLD:
-			if (button==OPEN)
+			if (button==KEYPAD_OPEN)
 				transitionTo (idx, RELEASED);
 			break;
 		case RELEASED:
diff --git a/src/Keypad.h b/src/Keypad.h
index 0648114..20560d3 100644
--- a/src/Keypad.h
+++ b/src/Keypad.h
@@ -52,8 +52,8 @@ do {							 \
 #endif
 
 
-#define OPEN LOW
-#define CLOSED HIGH
+#define KEYPAD_OPEN LOW    // Many libraries use this alias OPEN , and this cause issues
+#define KEYPAD_CLOSED HIGH  // Many libraries use this alias CLOSED , and this cause issues
 
 typedef char KeypadEvent;
 typedef unsigned int uint;