diff --git a/firmware/keyboard/ergodox/controller/mcp23018.c b/firmware/keyboard/ergodox/controller/mcp23018.c
index 7b78714..aa71d85 100644
--- a/firmware/keyboard/ergodox/controller/mcp23018.c
+++ b/firmware/keyboard/ergodox/controller/mcp23018.c
@@ -66,6 +66,15 @@
 #define  TWI_ADDR_WRITE  ( (TWI_ADDR<<1) | TW_WRITE )
 #define  TWI_ADDR_READ   ( (TWI_ADDR<<1) | TW_READ  )
 
+#ifdef ENABLE_LEFT_LED
+extern uint8_t _led_11_state;  // left red (top)
+extern uint8_t _led_12_state;  // left yellow (middle)
+extern uint8_t _led_13_state;  // left green (bottom)
+#define LED_11_BIT_SHIFT    7  // in A
+#define LED_12_BIT_SHIFT    6  // in B
+#define LED_13_BIT_SHIFT    7  // in B
+#endif
+
 // ----------------------------------------------------------------------------
 
 /**                                        functions/mcp23018__init/description
@@ -91,11 +100,21 @@ uint8_t mcp23018__init(void) {
     if (ret) goto out;  // make sure we got an ACK
     twi__send(IODIRA);
     #if OPT__MCP23018__DRIVE_ROWS
+#ifndef ENABLE_LEFT_LED
         twi__send(0b11111111);  // IODIRA
         twi__send(0b11000000);  // IODIRB
+#else
+        twi__send(0b01111111);  // IODIRA
+        twi__send(0b00000000);  // IODIRB
+#endif
     #elif OPT__MCP23018__DRIVE_COLUMNS
+#ifndef ENABLE_LEFT_LED
         twi__send(0b10000000);  // IODIRA
         twi__send(0b11111111);  // IODIRB
+#else
+        twi__send(0b00000000);  // IODIRA
+        twi__send(0b00111111);  // IODIRB
+#endif
     #endif
     twi__stop();
 
@@ -108,11 +127,21 @@ uint8_t mcp23018__init(void) {
     if (ret) goto out;  // make sure we got an ACK
     twi__send(GPPUA);
     #if OPT__MCP23018__DRIVE_ROWS
+#ifndef ENABLE_LEFT_LED
         twi__send(0b11111111);  // GPPUA
         twi__send(0b11000000);  // GPPUB
+#else
+        twi__send(0b01111111);  // GPPUA
+        twi__send(0b00000000);  // GPPUB
+#endif
     #elif OPT__MCP23018__DRIVE_COLUMNS
+#ifndef ENABLE_LEFT_LED
         twi__send(0b10000000);  // GPPUA
         twi__send(0b11111111);  // GPPUB
+#else
+        twi__send(0b00000000);  // GPPUA
+        twi__send(0b00111111);  // GPPUB
+#endif
     #endif
     twi__stop();
 
@@ -124,8 +153,13 @@ uint8_t mcp23018__init(void) {
     ret = twi__send(TWI_ADDR_WRITE);
     if (ret) goto out;  // make sure we got an ACK
     twi__send(OLATA);
+#ifndef ENABLE_LEFT_LED
     twi__send(0b11111111);  //OLATA
     twi__send(0b11111111);  //OLATB
+#else
+    twi__send(0b11111111 & ~(_led_11_state<<LED_11_BIT_SHIFT));  //OLATA
+    twi__send(0b11111111 & ~(_led_12_state<<LED_12_BIT_SHIFT) & ~(_led_13_state<<LED_13_BIT_SHIFT));  //OLATB
+#endif
 
 out:
     twi__stop();
@@ -171,7 +205,11 @@ uint8_t mcp23018__update_matrix(bool matrix[OPT__KB__ROWS][OPT__KB__COLUMNS]) {
             twi__start();
             twi__send(TWI_ADDR_WRITE);
             twi__send(GPIOB);
+#ifndef ENABLE_LEFT_LED
             twi__send( 0xFF & ~(1<<(5-row)) );
+#else
+            twi__send( 0xFF & ~(1<<(5-row)) & ~(_led_12_state<<LED_12_BIT_SHIFT) & ~(_led_13_state<<LED_13_BIT_SHIFT));
+#endif
             twi__stop();
 
             // read column data
@@ -193,7 +231,11 @@ uint8_t mcp23018__update_matrix(bool matrix[OPT__KB__ROWS][OPT__KB__COLUMNS]) {
         twi__start();
         twi__send(TWI_ADDR_WRITE);
         twi__send(GPIOB);
+#ifndef ENABLE_LEFT_LED
         twi__send(0xFF);
+#else
+        twi__send( 0xFF & ~(_led_12_state<<LED_12_BIT_SHIFT) & ~(_led_13_state<<LED_13_BIT_SHIFT));
+#endif
         twi__stop();
 
     #elif OPT__MCP23018__DRIVE_COLUMNS
@@ -203,7 +245,11 @@ uint8_t mcp23018__update_matrix(bool matrix[OPT__KB__ROWS][OPT__KB__COLUMNS]) {
             twi__start();
             twi__send(TWI_ADDR_WRITE);
             twi__send(GPIOA);
+#ifndef ENABLE_LEFT_LED
             twi__send( 0xFF & ~(1<<col) );
+#else
+            twi__send( 0xFF & ~(1<<col) & ~(_led_11_state<<LED_11_BIT_SHIFT));
+#endif
             twi__stop();
 
             // read row data
@@ -225,7 +271,11 @@ uint8_t mcp23018__update_matrix(bool matrix[OPT__KB__ROWS][OPT__KB__COLUMNS]) {
         twi__start();
         twi__send(TWI_ADDR_WRITE);
         twi__send(GPIOA);
+#ifndef ENABLE_LEFT_LED
         twi__send(0xFF);
+#else
+        twi__send( 0xFF & ~(_led_11_state<<LED_11_BIT_SHIFT));
+#endif
         twi__stop();
 
     #endif
diff --git a/firmware/keyboard/ergodox/led.c b/firmware/keyboard/ergodox/led.c
index 761089d..4a20941 100644
--- a/firmware/keyboard/ergodox/led.c
+++ b/firmware/keyboard/ergodox/led.c
@@ -25,6 +25,12 @@
  * not quite off
  */
 
+#ifdef ENABLE_LEFT_LED
+uint8_t _led_11_state = 0;  // left red (top)
+uint8_t _led_12_state = 0;  // left yellow (middle)
+uint8_t _led_13_state = 0;  // left green (bottom)
+#endif
+
 // ----------------------------------------------------------------------------
 
 void kb__led__on(uint8_t led) {
@@ -34,6 +40,11 @@ void kb__led__on(uint8_t led) {
         case 3: (DDRB |=  (1<<7)); break;  // bottommost
         case 4:                    break;
         case 5:                    break;
+#ifdef ENABLE_LEFT_LED
+        case 11: _led_11_state = 1; break;
+        case 12: _led_12_state = 1; break;
+        case 13: _led_13_state = 1; break;
+#endif	
     };
 }
 
@@ -44,6 +55,11 @@ void kb__led__off(uint8_t led) {
 	    case 3: (DDRB &= ~(1<<7)); break;  // bottommost
         case 4:                    break;
         case 5:                    break;
+#ifdef ENABLE_LEFT_LED
+        case 11: _led_11_state = 0; break;
+        case 12: _led_12_state = 0; break;
+        case 13: _led_13_state = 0; break;
+#endif	
     };
 }
 
@@ -54,6 +70,11 @@ void kb__led__set(uint8_t led, float n) {
         case 3: (OCR1C = (uint8_t)((n) * 0xFF)); break;  // bottommost
         case 4:                                  break;
         case 5:                                  break;
+#ifdef ENABLE_LEFT_LED
+        case 11:                                 break;
+        case 12:                                 break;
+        case 13:                                 break;
+#endif	
     };
 }
 
@@ -62,10 +83,15 @@ void kb__led__set(uint8_t led, float n) {
 bool kb__led__read(uint8_t led) {
     switch(led) {
         case 1: return (PINB & (1<<5));  // topmost
-	    case 2: return (PINB & (1<<6));  // middle
-	    case 3: return (PINB & (1<<7));  // bottommost
+        case 2: return (PINB & (1<<6));  // middle
+        case 3: return (PINB & (1<<7));  // bottommost
         case 4: ;
         case 5: ;
+#ifdef ENABLE_LEFT_LED
+        case 11: return(_led_11_state);
+        case 12: return(_led_12_state);
+        case 13: return(_led_13_state);
+#endif	
     };
     return false;
 }
@@ -75,11 +101,19 @@ bool kb__led__read(uint8_t led) {
 void kb__led__all_on(void) {
     for(int8_t i=1; i<=3; i++)
         kb__led__on(i);
+#ifdef ENABLE_LEFT_LED
+    for(int8_t i=11; i<=13; i++)
+        kb__led__on(i);
+#endif
 }
 
 void kb__led__all_off(void) {
     for(int8_t i=1; i<=3; i++)
         kb__led__off(i);
+#ifdef ENABLE_LEFT_LED
+    for(int8_t i=11; i<=13; i++)
+        kb__led__off(i);
+#endif
 }
 
 void kb__led__all_set(float n) {
diff --git a/firmware/main.c b/firmware/main.c
index 35cb578..42cc92b 100644
--- a/firmware/main.c
+++ b/firmware/main.c
@@ -69,6 +69,11 @@ int main(void) {
 
     kb__led__state__power_on();
 
+#ifdef ENABLE_LEFT_LED
+    // must do this once for led state to be pushed over
+    mcp23018__init();
+#endif
+
     usb__init();
     while (!usb__is_configured());
     kb__led__delay__usb_init();  // give the OS time to load drivers, etc.
diff --git a/firmware/makefile b/firmware/makefile
index c829ea8..a0465b2 100644
--- a/firmware/makefile
+++ b/firmware/makefile
@@ -64,6 +64,7 @@ SRC += $(wildcard $(CURDIR)/main.c)
 
 # -----------------------------------------------------------------------------
 
+CFLAGS += -DENABLE_LEFT_LED
 CFLAGS += -mmcu=$(MCU)      # processor type; must match real life
 CFLAGS += -DF_CPU=$(F_CPU)  # processor frequency; must match initialization
 			    #   in source