diff --git a/csharp/GildedRose.cs b/csharp/GildedRose.cs
index c60d97a0..38c86919 100644
--- a/csharp/GildedRose.cs
+++ b/csharp/GildedRose.cs
@@ -1,89 +1,87 @@
-using System.Collections.Generic;
+using System.Collections.Generic;
 
 namespace csharp
 {
     public class GildedRose
     {
-        IList<Item> Items;
-        public GildedRose(IList<Item> Items)
+        private readonly IList<Item> _items;
+        
+        public GildedRose(IList<Item> items)
         {
-            this.Items = Items;
+            _items = items;
         }
 
         public void UpdateQuality()
         {
-            for (var i = 0; i < Items.Count; i++)
+            foreach (var item in _items)
             {
-                if (Items[i].Name != "Aged Brie" && Items[i].Name != "Backstage passes to a TAFKAL80ETC concert")
+                UpdateItemQuality(item);
+                UpdateItemSellIn(item);
+            }
+        }
+        
+        private void UpdateItemQuality(Item item)
+        {
+            if (item.Name == "Aged Brie")
+            {
+                IncreaseQuality(item);
+                if (item.SellIn < 0)
                 {
-                    if (Items[i].Quality > 0)
-                    {
-                        if (Items[i].Name != "Sulfuras, Hand of Ragnaros")
-                        {
-                            Items[i].Quality = Items[i].Quality - 1;
-                        }
-                    }
+                    IncreaseQuality(item);
                 }
-                else
+            }
+            else if (item.Name == "Backstage passes to a TAFKAL80ETC concert")
+            {
+                IncreaseQuality(item);
+                if (item.SellIn < 11)
                 {
-                    if (Items[i].Quality < 50)
-                    {
-                        Items[i].Quality = Items[i].Quality + 1;
-
-                        if (Items[i].Name == "Backstage passes to a TAFKAL80ETC concert")
-                        {
-                            if (Items[i].SellIn < 11)
-                            {
-                                if (Items[i].Quality < 50)
-                                {
-                                    Items[i].Quality = Items[i].Quality + 1;
-                                }
-                            }
-
-                            if (Items[i].SellIn < 6)
-                            {
-                                if (Items[i].Quality < 50)
-                                {
-                                    Items[i].Quality = Items[i].Quality + 1;
-                                }
-                            }
-                        }
-                    }
+                    IncreaseQuality(item);
                 }
-
-                if (Items[i].Name != "Sulfuras, Hand of Ragnaros")
+                if (item.SellIn < 6)
                 {
-                    Items[i].SellIn = Items[i].SellIn - 1;
+                    IncreaseQuality(item);
                 }
-
-                if (Items[i].SellIn < 0)
+                if (item.SellIn < 0)
                 {
-                    if (Items[i].Name != "Aged Brie")
-                    {
-                        if (Items[i].Name != "Backstage passes to a TAFKAL80ETC concert")
-                        {
-                            if (Items[i].Quality > 0)
-                            {
-                                if (Items[i].Name != "Sulfuras, Hand of Ragnaros")
-                                {
-                                    Items[i].Quality = Items[i].Quality - 1;
-                                }
-                            }
-                        }
-                        else
-                        {
-                            Items[i].Quality = Items[i].Quality - Items[i].Quality;
-                        }
-                    }
-                    else
-                    {
-                        if (Items[i].Quality < 50)
-                        {
-                            Items[i].Quality = Items[i].Quality + 1;
-                        }
-                    }
+                    item.Quality = 0;
                 }
             }
+            else if (item.Name == "Sulfuras, Hand of Ragnaros")
+            {
+                // Do nothing, the item's quality and sell-in never change.
+            }
+            else
+            {
+                DecreaseQuality(item);
+                if (item.SellIn < 0)
+                {
+                    DecreaseQuality(item);
+                }
+            }
+        }
+        
+        private void IncreaseQuality(Item item)
+        {
+            if (item.Quality < 50)
+            {
+                item.Quality++;
+            }
+        }
+        
+        private void DecreaseQuality(Item item)
+        {
+            if (item.Quality > 0)
+            {
+                item.Quality--;
+            }
+        }
+        
+        private void UpdateItemSellIn(Item item)
+        {
+            if (item.Name != "Sulfuras, Hand of Ragnaros")
+            {
+                item.SellIn--;
+            }
         }
     }
 }