diff --git a/src/RomanNumerals.java b/src/RomanNumerals.java
index 20904f0..e709a69 100644
--- a/src/RomanNumerals.java
+++ b/src/RomanNumerals.java
@@ -1,8 +1,36 @@
 
 public class RomanNumerals {
 	public int convertToInteger(String romanNum) {
-		// To be Implemented
-		return 0;
+
+		int result = 0;
+		int currentDigit = 0;
+		int previousDigit = 0;
 		
+    	for (int i = romanNum.length() - 1; i >= 0; i--) {
+    		char romanDigit = romanNum.charAt(i);
+
+    		if (romanDigit == 'I') {
+        		currentDigit = 1;
+       		} else if (romanDigit == 'V') {
+       			currentDigit = 5;
+       		} else if (romanDigit == 'X') {
+       			currentDigit = 10;
+        	} else if (romanDigit == 'L') {
+        		currentDigit = 50;
+       		} else if (romanDigit == 'C') {
+       			currentDigit = 100;
+       		} else if (romanDigit == 'D') {
+       			currentDigit = 500;
+       		} else if (romanDigit == 'M') {
+       			currentDigit = 1000;
+       		}
+    		if (previousDigit > currentDigit) {
+    			result -= currentDigit;
+    		} else {
+    			result += currentDigit;
+    		}
+    		previousDigit = currentDigit;
+    	}
+    	return result;
 	}
 }
diff --git a/tests/TestRomanNumerals.java b/tests/TestRomanNumerals.java
index 5d1de75..1f34c35 100644
--- a/tests/TestRomanNumerals.java
+++ b/tests/TestRomanNumerals.java
@@ -4,9 +4,103 @@
 
 public class TestRomanNumerals {
 
+	// Test "prime" values
 	@Test
-	public void test() {
-		fail("Not yet implemented");
+	public void testOnes_one() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("I");
+		assertEquals(1, value);
 	}
 
+	@Test
+	public void testFive() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("V");
+		assertEquals(5, value);
+	}
+
+	@Test
+	public void testTen() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("X");
+		assertEquals(10, value);
+	}
+	
+	@Test
+	public void testFifty() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("L");
+		assertEquals(50, value);
+	}
+
+	@Test
+	public void testHundred() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("C");
+		assertEquals(100, value);
+	}
+
+	@Test
+	public void testFiveHundred() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("D");
+		assertEquals(500, value);
+	}
+	
+	@Test
+	public void testThousand() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("M");
+		assertEquals(1000, value);
+	}
+	
+	// Test "odd, under and over"
+	@Test
+	public void testFour() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("IV");
+		assertEquals(4, value);
+	}
+
+	@Test
+	public void testNine() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("IX");
+		assertEquals(9, value);
+	}
+
+	@Test
+	public void testThree() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("III");
+		assertEquals(3, value);
+	}
+
+	@Test
+	public void testHundredNine() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("CIX");
+		assertEquals(109, value);
+	}
+
+	@Test
+	public void testTwoThousandSixteen() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("MMXVI");
+		assertEquals(2016, value);
+	}
+
+	@Test
+	public void testNineHundredEightyEight() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("DCCCCLXXXVIII");
+		assertEquals(988, value);
+	}
+
+	@Test
+	public void testNineThousandNineHundredNinetyNine() {
+		RomanNumerals rn = new RomanNumerals();
+		int value = rn.convertToInteger("MMMMMMMMMIM");
+		assertEquals(9999, value);
+	}
 }