diff --git a/src/MCP23017.cpp b/src/MCP23017.cpp
index b36cb8f..edd69cd 100644
--- a/src/MCP23017.cpp
+++ b/src/MCP23017.cpp
@@ -5,6 +5,11 @@ MCP23017::MCP23017(uint8_t address, TwoWire& bus) {
 	_bus = &bus;
 }
 
+MCP23017::MCP23017(TwoWire& bus) {
+	_deviceAddr = MCP23017_I2C_ADDRESS;
+	_bus = &bus;
+}
+
 MCP23017::~MCP23017() {}
 
 void MCP23017::init()
@@ -25,6 +30,17 @@ void MCP23017::init()
 	writeRegister(MCP23017Register::GPPU_A, 0xFF, 0xFF);
 }
 
+void MCP23017::begin()
+{
+	init();
+}
+
+void MCP23017::begin(uint8_t address)
+{
+	_deviceAddr = address;
+	begin();
+}
+
 void MCP23017::portMode(MCP23017Port port, uint8_t directions, uint8_t pullups, uint8_t inverted)
 {
 	writeRegister(MCP23017Register::IODIR_A + port, directions);
diff --git a/src/MCP23017.h b/src/MCP23017.h
index e665108..3427261 100644
--- a/src/MCP23017.h
+++ b/src/MCP23017.h
@@ -3,6 +3,7 @@
 #include <Arduino.h>
 #include <Wire.h>
 
+#define MCP23017_I2C_ADDRESS 0x20    ///< The default I2C address of MCP23017.
 #define _MCP23017_INTERRUPT_SUPPORT_ ///< Enables support for MCP23017 interrupts.
 
 enum class MCP23017Port : uint8_t
@@ -65,10 +66,24 @@ class MCP23017
 	 * Instantiates a new instance to interact with a MCP23017 at the specified address.
 	 */
 	MCP23017(uint8_t address, TwoWire& bus = Wire);
+	/**
+	 * Instantiates a new instance to interact with a MCP23017 at the
+	 * MCP23017_I2C_ADDRESS default.
+	 */
+	MCP23017(TwoWire& bus = Wire);
 	~MCP23017();
 #ifdef _DEBUG
 	void debug();
 #endif
+	/**
+	 * Uses the I2C address set during construction. Implicitly calls init().
+	 */
+	void begin();
+	/**
+	 * Overrides the I2C address set by the constructor. Implicitly calls begin().
+
+	 */
+	void begin(uint8_t address);
 	/**
 	 * Initializes the chip with the default configuration.
 	 * Enables Byte mode (IOCON.BANK = 0 and IOCON.SEQOP = 1).
@@ -221,4 +236,4 @@ class MCP23017
 	void clearInterrupts(uint8_t& portA, uint8_t& portB);
 
 #endif
-};
\ No newline at end of file
+};