diff --git a/minesweeper/src/main/java/edu/pdx/cs410J/katas/Minesweeper.java b/minesweeper/src/main/java/edu/pdx/cs410J/katas/Minesweeper.java
index 3fe6bf0..e4d3ac6 100644
--- a/minesweeper/src/main/java/edu/pdx/cs410J/katas/Minesweeper.java
+++ b/minesweeper/src/main/java/edu/pdx/cs410J/katas/Minesweeper.java
@@ -2,8 +2,15 @@
 
 public class Minesweeper  {
 
-  public Minesweeper(int row, int column) {
+  private final Integer rowCount;
+  private final Integer columnCount;
 
+  public Minesweeper(int rowCount, int columnCount) {
+    if (rowCount == 0 || columnCount == 0)
+        throw new ZeroSizedBoardException();
+
+    this.rowCount = rowCount;
+    this.columnCount = columnCount;
   }
 
   public void addRow(String row) {
diff --git a/minesweeper/src/main/java/edu/pdx/cs410J/katas/ZeroSizedBoardException.java b/minesweeper/src/main/java/edu/pdx/cs410J/katas/ZeroSizedBoardException.java
index 714ed09..52636ff 100644
--- a/minesweeper/src/main/java/edu/pdx/cs410J/katas/ZeroSizedBoardException.java
+++ b/minesweeper/src/main/java/edu/pdx/cs410J/katas/ZeroSizedBoardException.java
@@ -1,4 +1,4 @@
 package edu.pdx.cs410J.katas;
 
-public class ZeroSizedBoardException extends Throwable {
+public class ZeroSizedBoardException extends RuntimeException {
 }