diff --git a/ICD.Common.Utils.Tests/Collections/BiDictionaryTest.cs b/ICD.Common.Utils.Tests/Collections/BiDictionaryTest.cs
new file mode 100644
index 0000000..2820615
--- /dev/null
+++ b/ICD.Common.Utils.Tests/Collections/BiDictionaryTest.cs
@@ -0,0 +1,219 @@
+using System;
+using ICD.Common.Utils.Collections;
+using NUnit.Framework;
+
+namespace ICD.Common.Utils.Tests.Collections
+{
+	[TestFixture]
+	public sealed class BiDictionaryTest
+	{
+		#region Properties
+
+		[Test]
+		public void CountTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			dict.Set(1, "10");
+			dict.Set(2, "10");
+			dict.Set(3, "30");
+
+			Assert.AreEqual(2, dict.Count);
+		}
+
+		[Test]
+		public void KeysTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			dict.Set(1, "10");
+			dict.Set(2, "10");
+			dict.Set(3, "30");
+
+			Assert.AreEqual(2, dict.Keys.Count);
+
+			Assert.IsTrue(dict.Keys.Contains(2));
+			Assert.IsTrue(dict.Keys.Contains(3));
+		}
+
+		[Test]
+		public void ValuesTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			dict.Set(1, "10");
+			dict.Set(1, "20");
+			dict.Set(3, "30");
+
+			Assert.AreEqual(2, dict.Values.Count);
+
+			Assert.IsTrue(dict.Values.Contains("20"));
+			Assert.IsTrue(dict.Values.Contains("30"));
+		}
+
+		#endregion
+
+		#region Methods
+
+		[Test]
+		public void ClearTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			dict.Set(1, "10");
+			dict.Set(1, "20");
+			dict.Set(3, "30");
+
+			Assert.AreEqual(2, dict.Count);
+
+			dict.Clear();
+
+			Assert.AreEqual(0, dict.Count);
+		}
+
+		[Test]
+		public void ContainsKeyTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			Assert.IsFalse(dict.ContainsKey(1));
+
+			dict.Set(1, "10");
+
+			Assert.IsTrue(dict.ContainsKey(1));
+		}
+
+		[Test]
+		public void ContainsValueTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			Assert.IsFalse(dict.ContainsValue("10"));
+
+			dict.Set(1, "10");
+
+			Assert.IsTrue(dict.ContainsValue("10"));
+		}
+
+		[Test]
+		public void AddTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			dict.Add(1, "10");
+
+			Assert.AreEqual(1, dict.Count);
+
+			Assert.Throws<ArgumentException>(() => dict.Add(1, "10"));
+			Assert.Throws<ArgumentException>(() => dict.Add(1, "20"));
+			Assert.Throws<ArgumentException>(() => dict.Add(2, "10"));
+
+			Assert.DoesNotThrow(() => dict.Add(2, "20"));
+
+			Assert.AreEqual(2, dict.Count);
+		}
+
+		[Test]
+		public void SetTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			dict.Set(1, "10");
+			dict.Set(1, "20");
+			dict.Set(3, "30");
+
+			Assert.AreEqual("20", dict.GetValue(1));
+			Assert.AreEqual("30", dict.GetValue(3));
+
+			Assert.AreEqual(1, dict.GetKey("20"));
+			Assert.AreEqual(3, dict.GetKey("30"));
+		}
+
+		[Test]
+		public void GetKeyTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			dict.Set(1, "10");
+			dict.Set(1, "20");
+			dict.Set(3, "30");
+
+			Assert.AreEqual(1, dict.GetKey("20"));
+			Assert.AreEqual(3, dict.GetKey("30"));
+		}
+
+		[Test]
+		public void GetValueTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			dict.Set(1, "10");
+			dict.Set(1, "20");
+			dict.Set(3, "30");
+
+			Assert.AreEqual("20", dict.GetValue(1));
+			Assert.AreEqual("30", dict.GetValue(3));
+		}
+
+		[Test]
+		public void RemoveKeyTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			dict.Add(1, "10");
+
+			Assert.AreEqual(1, dict.Count);
+
+			dict.RemoveKey(1);
+
+			Assert.AreEqual(0, dict.Count);
+		}
+
+		[Test]
+		public void RemoveValueTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			dict.Add(1, "10");
+
+			Assert.AreEqual(1, dict.Count);
+
+			dict.RemoveValue("10");
+
+			Assert.AreEqual(0, dict.Count);
+		}
+
+		[Test]
+		public void TryGetValueTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			string value;
+			Assert.IsFalse(dict.TryGetValue(1, out value));
+			// ReSharper disable once ExpressionIsAlwaysNull
+			Assert.AreEqual(null, value);
+
+			dict.Add(1, "10");
+
+			Assert.IsTrue(dict.TryGetValue(1, out value));
+			Assert.AreEqual("10", value);
+		}
+
+		[Test]
+		public void TryGetKeyTest()
+		{
+			BiDictionary<int, string> dict = new BiDictionary<int, string>();
+
+			int value;
+			Assert.IsFalse(dict.TryGetKey("10", out value));
+			Assert.AreEqual(0, value);
+
+			dict.Add(1, "10");
+
+			Assert.IsTrue(dict.TryGetKey("10", out value));
+			Assert.AreEqual(1, value);
+		}
+
+		#endregion
+	}
+}