diff --git a/domain-model.md b/domain-model.md
index 653f474..976c457 100644
--- a/domain-model.md
+++ b/domain-model.md
@@ -1 +1,28 @@
-#Domain Models In Here
\ No newline at end of file
+#Domain Models In Here
+
+## Exercise 1
+
+User Story 1
+
+```
+As a supermarket shopper,
+So that I can pay for products at checkout,
+I'd like to be able to know the total cost of items in my basket.
+```
+
+User Story 2
+
+```
+As an organised individual,
+So that I can evaluate my shopping habits,
+I'd like to see an itemised receipt that includes the name and price of the products
+I bought as well as the quantity, and a total cost of my basket.
+```
+
+| Classes      | Methods                                   | Scenario                                                        | Outputs                               |
+|--------------|-------------------------------------------|-----------------------------------------------------------------|---------------------------------------|
+| `Customer`   | GetTotal(Basket basket)                   | If basket is not empty                                          | Total cost of basket                  |
+|              |                                           | If basket is empty                                              | 0                                     |
+| `Basket`     | GetTotal(Dictionary<string, Tuple<int, int>>)  | If basket is not empty                                          | Total cost of basket                  |
+|              |                                           | If basket is empty                                              | 0                                     |
+| `Product`    |                                           |                                                                 |                                       |
diff --git a/exercise2.md b/exercise2.md
index e8c8e0d..8799ca8 100644
--- a/exercise2.md
+++ b/exercise2.md
@@ -62,6 +62,6 @@ I'd like to be able to know the total cost of items in my basket.
 
 | Classes  | Members                                                            | Methods                          | Scenario                                                   | Outputs |
 |----------|--------------------------------------------------------------------|----------------------------------|------------------------------------------------------------|---------|
-| `Basket` | `HashMap<String, int> items` (key is product name, value is price) | `add(String product, int price)` | Item with the provided name *is not* already in the basket | true    |
+| `Basket` | `Dictionary<String, int> items` (key is product name, value is price) | `add(String product, int price)` | Item with the provided name *is not* already in the basket | true    |
 |          |                                                                    |                                  | Item with the provided name *is* already in the basket     | false   |
 |          |                                                                    | `total()`                        |                                                            | int     |
diff --git a/tdd-domain-modelling.CSharp.Main/Basket.cs b/tdd-domain-modelling.CSharp.Main/Basket.cs
new file mode 100644
index 0000000..e84999c
--- /dev/null
+++ b/tdd-domain-modelling.CSharp.Main/Basket.cs
@@ -0,0 +1,28 @@
+
+
+namespace tdd_domain_modelling.CSharp.Main
+{
+    public class Basket
+    {
+        private Dictionary<string, int> _basket = new ();
+        public Dictionary<string, int> basket { get { return _basket; } }
+
+        public bool Add(string product, int price)
+        {
+            if (basket.ContainsKey(product)) return false;
+            _basket.Add(product, price);
+            return true;
+        }
+
+        public int Total()
+        {
+            int count = 0;
+            foreach (var item in _basket)
+            {
+                count += item.Value;
+            }
+
+            return count;
+        }
+    }
+}
\ No newline at end of file
diff --git a/tdd-domain-modelling.CSharp.Test/BasketTests.cs b/tdd-domain-modelling.CSharp.Test/BasketTests.cs
new file mode 100644
index 0000000..7c0d1af
--- /dev/null
+++ b/tdd-domain-modelling.CSharp.Test/BasketTests.cs
@@ -0,0 +1,103 @@
+using NUnit.Framework;
+using tdd_domain_modelling.CSharp.Main;
+
+namespace tdd_domain_modelling.CSharp.Test
+{
+    public class BasketTests
+    {
+        [Test]
+        public void AddTest()
+        {
+            // arrange
+            Basket basket = new();
+            string product = "Pear";
+            int price = 10;
+            // act
+            var result = basket.Add(product, price);
+            // assert
+            Assert.True(result);
+        }
+        [Test]
+        public void AddSeveralTest()
+        {
+            // arrange
+            Basket basket = new();
+            string product1 = "Pear";
+            int price1 = 10;
+            string product2 = "Coffee";
+            int price2 = 55;
+            // act
+            var result1 = basket.Add(product1, price1);
+            var result2 = basket.Add(product2, price2);
+
+            // assert
+            Assert.True(result1);
+            Assert.True(result2);
+
+        }
+
+        [Test]
+        public void AddConflictingTest()
+        {
+            // arrange
+            Basket basket = new();
+            string product = "Pear";
+            int price = 10;
+            // act
+            var result1 = basket.Add(product, price);
+            var result2 = basket.Add(product, price);
+
+            // assert
+            Assert.True(result1);
+            Assert.False(result2);
+        }
+
+        [Test]
+        public void TotalZeroItemsTest()
+        {
+            Basket basket = new();
+
+            int result = basket.Total();
+            int expectedResult = 0;
+
+            Assert.AreEqual(expectedResult, result);
+
+        }
+
+        [Test]
+        public void TotalOneItemTest()
+        {
+            // arrange
+            Basket basket = new();
+            string product = "Pear";
+            int price = 10;
+            // act
+            basket.Add(product, price);
+            var result = basket.Total();
+            int expectedResult = price;
+
+            Assert.AreEqual(expectedResult, result);
+
+        }
+
+        [Test]
+        public void TotalSeveralItemsTest()
+        {
+            // arrange
+            Basket basket = new();
+            string product1 = "Pear";
+            int price1 = 10;
+            string product2 = "Coffee";
+            int price2 = 55;
+            // act
+            basket.Add(product1, price1);
+            basket.Add(product2, price2);
+
+            var result = basket.Total();
+            int expectedResult = price1 + price2;
+
+            Assert.AreEqual(expectedResult, result);
+
+        }
+    }
+}