diff --git a/src/RomanNumerals.java b/src/RomanNumerals.java
index 20904f0..d0243b4 100644
--- a/src/RomanNumerals.java
+++ b/src/RomanNumerals.java
@@ -1,8 +1,73 @@
 
+
 public class RomanNumerals {
-	public int convertToInteger(String romanNum) {
-		// To be Implemented
-		return 0;
+	public int convertToInteger(String romanNum) throws RomanNumeralsException {		
+		
+		int length=romanNum.length();
+		int i=0;
+		int number = 0;
+		
+		if (romanNum.indexOf("IIII") >= 0)
+			throw new RomanNumeralsException("More than three I's in row is not accepted.");
+		else if (romanNum.indexOf("XXXX") >= 0)
+			throw new RomanNumeralsException("More than three X's in row is not accepted.");
+		else if (romanNum.indexOf("CCCC") >= 0)
+			throw new RomanNumeralsException("More than three C's in row is not accepted.");
+		else if (romanNum.indexOf("MMMM") >= 0)
+			throw new RomanNumeralsException("More than three M's in row is not accepted.");
+		
+		if (romanNum.indexOf("VV") >= 0)
+			throw new RomanNumeralsException("More than two V's in row is not accepted.");
+		else if (romanNum.indexOf("LL") >= 0)
+			throw new RomanNumeralsException("More than two L's in row is not accepted.");
+		else if (romanNum.indexOf("DD") >= 0)
+			throw new RomanNumeralsException("More than two D's in row is not accepted.");
+		
+		// todo: two or more smaller before big results exception
+		
+		while(i<length)
+	    {
+			
+			if ((i+1)<length && valueOfLetter(romanNum.charAt(i)) < valueOfLetter(romanNum.charAt(i+1))){
+				number += valueOfLetter(romanNum.charAt(i+1)) - valueOfLetter(romanNum.charAt(i));
+				i+=2;
+			}
+			else {
+				number += valueOfLetter(romanNum.charAt(i));
+				i++;
+			}
+	    }
+		
+		return number;
+	}
+	
+	private int valueOfLetter(Character  letter) {
+		int number = 0;
+		
+		switch (letter) {
+		case 'I':
+			number = 1;
+            break;
+        case 'V':
+        	number = 5;
+            break;
+        case 'X':
+        	number = 10;
+            break;
+        case 'L':
+        	number = 50;
+            break;
+        case 'C':
+        	number = 100;
+            break;  
+        case 'D':
+        	number = 500;
+            break;   
+        case 'M':
+        	number = 1000;
+            break;  
+		}
 		
+		return number;
 	}
 }
diff --git a/src/RomanNumeralsException.java b/src/RomanNumeralsException.java
new file mode 100644
index 0000000..85dbcb9
--- /dev/null
+++ b/src/RomanNumeralsException.java
@@ -0,0 +1,7 @@
+
+public class RomanNumeralsException extends Exception {
+	public RomanNumeralsException(String message)
+	  {
+	    super(message);
+	  }
+}
diff --git a/tests/TestRomanNumerals.java b/tests/TestRomanNumerals.java
index 5d1de75..a959dcd 100644
--- a/tests/TestRomanNumerals.java
+++ b/tests/TestRomanNumerals.java
@@ -1,12 +1,152 @@
 import static org.junit.Assert.*;
 
+import org.junit.Assert;
 import org.junit.Test;
 
 public class TestRomanNumerals {
+	
+	RomanNumerals roman = new RomanNumerals();
 
 	@Test
-	public void test() {
-		fail("Not yet implemented");
+	public void test_convert_I_to_1() throws RomanNumeralsException {
+		int i = roman.convertToInteger("I");
+		assertEquals(1, i);
+	}
+	
+	@Test
+	public void test_convert_II_to_2() throws RomanNumeralsException {
+		int i = roman.convertToInteger("II");
+		assertEquals(2, i);
+	}
+	
+	@Test
+	public void test_convert_III_to_3() throws RomanNumeralsException {
+		int i = roman.convertToInteger("III");
+		assertEquals(3, i);
+	}
+	
+	@Test
+	public void test_convert_IV_to_4() throws RomanNumeralsException {
+		int i = roman.convertToInteger("IV");
+		assertEquals(4, i);
+	}
+
+	@Test
+	public void test_convert_V_to_5() throws RomanNumeralsException {
+		int i = roman.convertToInteger("V");
+		assertEquals(5, i);
+	}
+	
+	@Test
+	public void test_convert_VI_to_6() throws RomanNumeralsException {
+		int i = roman.convertToInteger("VI");
+		assertEquals(6, i);
+	}
+	
+	@Test
+	public void test_convert_VII_to_7() throws RomanNumeralsException {
+		int i = roman.convertToInteger("VII");
+		assertEquals(7, i);
+	}
+	
+	@Test
+	public void test_convert_VIII_to_8() throws RomanNumeralsException {
+		int i = roman.convertToInteger("VIII");
+		assertEquals(8, i);
+	}
+	
+	@Test
+	public void test_convert_IX_to_9() throws RomanNumeralsException {
+		int i = roman.convertToInteger("IX");
+		assertEquals(9, i);
+	}
+	
+	@Test
+	public void test_convert_X_to_10() throws RomanNumeralsException {
+		int i = roman.convertToInteger("X");
+		assertEquals(10, i);
+	}
+	
+	@Test
+	public void test_convert_XX_to_20() throws RomanNumeralsException {
+		int i = roman.convertToInteger("XX");
+		assertEquals(20, i);
+	}
+	
+	@Test
+	public void test_convert_XL_to_40() throws RomanNumeralsException {
+		int i = roman.convertToInteger("XL");
+		assertEquals(40, i);
+	}
+	
+	@Test
+	public void test_convert_C_to_100() throws RomanNumeralsException {
+		int i = roman.convertToInteger("C");
+		assertEquals(100, i);
+	}
+	
+	@Test
+	public void test_convert_D_to_500() throws RomanNumeralsException {
+		int i = roman.convertToInteger("D");
+		assertEquals(500, i);
+	}
+	
+	@Test
+	public void test_convert_M_to_1000() throws RomanNumeralsException {
+		int i = roman.convertToInteger("M");
+		assertEquals(1000, i);
+	}
+	
+	@Test
+	public void test_convert_MCMLXXXIV_to_1984() throws RomanNumeralsException {
+		int i = roman.convertToInteger("MCMLXXXIV");
+		assertEquals(1984, i);
+	}
+	
+	@Test
+	public void test_convert_MMXIV_to_2014() throws RomanNumeralsException {
+		int i = roman.convertToInteger("MMXIV");
+		assertEquals(2014, i);
+	}
+	
+	@Test(expected=RomanNumeralsException.class)
+	public void test_convert_XXC_throws_exception() throws RomanNumeralsException {
+		int i = roman.convertToInteger("XXC");
+	}
+	
+	@Test(expected=RomanNumeralsException.class)
+	public void test_convert_IIIIM_throws_exception() throws RomanNumeralsException {
+		int i = roman.convertToInteger("IIIIM");
+	}
+	
+	@Test(expected=RomanNumeralsException.class)
+	public void test_convert_XXXXM_throws_exception() throws RomanNumeralsException {
+		int i = roman.convertToInteger("XXXXM");
+	}
+	
+	@Test(expected=RomanNumeralsException.class)
+	public void test_convert_CCCCM_throws_exception() throws RomanNumeralsException {
+		int i = roman.convertToInteger("CCCCM");
+	}
+	
+	@Test(expected=RomanNumeralsException.class)
+	public void test_convert_MMMMM_throws_exception() throws RomanNumeralsException {
+		int i = roman.convertToInteger("MMMMM");
+	}
+	
+	@Test(expected=RomanNumeralsException.class)
+	public void test_convert_VV_throws_exception() throws RomanNumeralsException {
+		int i = roman.convertToInteger("VV");
+	}
+	
+	@Test(expected=RomanNumeralsException.class)
+	public void test_convert_LL_throws_exception() throws RomanNumeralsException {
+		int i = roman.convertToInteger("LL");
+	}
+	
+	@Test(expected=RomanNumeralsException.class)
+	public void test_convert_DD_throws_exception() throws RomanNumeralsException {
+		int i = roman.convertToInteger("DD");
 	}
 
 }