diff --git a/UnityProject/Assembly-CSharp-Editor.csproj b/UnityProject/Assembly-CSharp-Editor.csproj
index 45876d2..83d906e 100644
--- a/UnityProject/Assembly-CSharp-Editor.csproj
+++ b/UnityProject/Assembly-CSharp-Editor.csproj
@@ -66,6 +66,7 @@
      <Compile Include="Assets\Editor\SpectrumGeneratorEditMode.cs" />
      <Compile Include="Assets\Editor\StateManagerEditor.cs" />
      <Compile Include="Assets\Editor\UnitTest\UnitTest_ChangeObserver.cs" />
+     <Compile Include="Assets\Editor\UnitTest\UnitTest_Holder.cs" />
      <Compile Include="Assets\Editor\UnitTest\UnitTest_RectangularSelection.cs" />
      <Compile Include="Assets\Editor\UnitTest\UnitTest_SpectrumGeneratorEditMode.cs" />
      <Compile Include="Assets\Editor\UnitTest\UnitTest_SpectrumGeneratorPlayMode.cs" />
diff --git a/UnityProject/Assembly-CSharp.csproj b/UnityProject/Assembly-CSharp.csproj
index 5426df1..173e777 100644
--- a/UnityProject/Assembly-CSharp.csproj
+++ b/UnityProject/Assembly-CSharp.csproj
@@ -74,6 +74,7 @@
      <Compile Include="Assets\Scenes\Examples\TimbreID\script\IdToText.cs" />
      <Compile Include="Assets\Scenes\Examples\VisualEffectGraph\script\FlareBind.cs" />
      <Compile Include="Assets\Scenes\Examples\VisualEffectGraph\script\SmokeBind.cs" />
+     <Compile Include="Assets\Scripts\Math\Holder.cs" />
      <Compile Include="Assets\Scripts\Math\Smoother.cs" />
      <Compile Include="Assets\Scripts\Math\Threshold.cs" />
      <Compile Include="Assets\Scripts\PdConnection\DspController.cs" />
diff --git a/UnityProject/Assets/Editor/UnitTest/UnitTest_Holder.cs b/UnityProject/Assets/Editor/UnitTest/UnitTest_Holder.cs
new file mode 100644
index 0000000..a18819f
--- /dev/null
+++ b/UnityProject/Assets/Editor/UnitTest/UnitTest_Holder.cs
@@ -0,0 +1,62 @@
+using NUnit.Framework;
+
+namespace cylvester
+{
+    [TestFixture]
+    public class UnitTest_Holder
+    {
+        [Test]
+        public void Construction_capacity()
+        {
+            var holder = new Holder<int>(2);
+            
+            holder.Add(1);
+            holder.Add(2);
+            holder.Add(3);
+
+            Assert.AreEqual(0, holder.IndexOf(1));
+            Assert.AreEqual(1, holder.IndexOf(2));
+            Assert.IsNull(holder.IndexOf(3));
+        }
+
+        [Test]
+        public void Add()
+        {
+            var holder = new Holder<int>(2);
+            holder.Add(102);
+            
+            Assert.AreEqual(0, holder.IndexOf(102));
+            Assert.IsNull(holder.IndexOf(103));
+        }
+        
+        [Test]
+        public void Add_return()
+        {
+            var holder = new Holder<int>(2);
+            Assert.IsTrue(holder.Add(102));
+            Assert.IsTrue(holder.Add(103));
+            Assert.IsFalse(holder.Add(103));
+        }
+
+        [Test]
+        public void Add_unique()
+        {
+            var holder = new Holder<int>(2);
+            holder.Add(102);
+            holder.Add(102); // doesn't affect
+            holder.Add(103);
+            
+            Assert.IsNull(holder.IndexOf(103));
+        }
+        
+        [Test]
+        public void Remove()
+        {
+            var holder = new Holder<int>(2);
+            holder.Add(102);
+            holder.Remove(102);
+
+            Assert.IsNull(holder.IndexOf(102));
+        }
+    }
+}
\ No newline at end of file
diff --git a/UnityProject/Assets/Editor/UnitTest/UnitTest_Holder.cs.meta b/UnityProject/Assets/Editor/UnitTest/UnitTest_Holder.cs.meta
new file mode 100644
index 0000000..cb588ee
--- /dev/null
+++ b/UnityProject/Assets/Editor/UnitTest/UnitTest_Holder.cs.meta
@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: e41847d6d84d439e858e4eadb0232998
+timeCreated: 1572778377
\ No newline at end of file
diff --git a/UnityProject/Assets/Scripts/Math/Holder.cs b/UnityProject/Assets/Scripts/Math/Holder.cs
new file mode 100644
index 0000000..0db5e5d
--- /dev/null
+++ b/UnityProject/Assets/Scripts/Math/Holder.cs
@@ -0,0 +1,45 @@
+using System;
+using System.Collections.Generic;
+
+namespace cylvester
+{
+    public class Holder<T>  where T : IEquatable<T>
+    {
+        private readonly List<T> elements_;
+        private readonly int capacity_;
+        
+        public Holder(int capacity)
+        {
+            capacity_ = capacity;
+            elements_ = new List<T>();
+        }
+
+        public bool Add(T newElement)
+        {
+            if (elements_.Count == capacity_)
+                return false;
+
+            if (elements_.Contains(newElement))
+                return false;
+            
+            elements_.Add(newElement);
+            return true;
+        }
+
+        public bool Exist(T element)
+        {
+            return elements_.Contains(element);
+        }
+        
+        public int? IndexOf(T element)
+        {
+            var index = elements_.FindIndex(e => e.Equals(element));
+            return (index < 0) ? (int?) null : index;
+        }
+        
+        public void Remove(T element)
+        {
+            elements_.Remove(element);
+        }
+    }
+}
\ No newline at end of file
diff --git a/UnityProject/Assets/Scripts/Math/Holder.cs.meta b/UnityProject/Assets/Scripts/Math/Holder.cs.meta
new file mode 100644
index 0000000..cfa141f
--- /dev/null
+++ b/UnityProject/Assets/Scripts/Math/Holder.cs.meta
@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: 200646bf9dc64be3905b4ac8dfef1634
+timeCreated: 1572777412
\ No newline at end of file
diff --git a/UnityProject/Assets/Scripts/UnitTest.meta b/UnityProject/Assets/Scripts/UnitTest.meta
deleted file mode 100644
index 64e07e5..0000000
--- a/UnityProject/Assets/Scripts/UnitTest.meta
+++ /dev/null
@@ -1,8 +0,0 @@
-fileFormatVersion: 2
-guid: 14b20e54517dff5419ed18c623ac9653
-folderAsset: yes
-DefaultImporter:
-  externalObjects: {}
-  userData: 
-  assetBundleName: 
-  assetBundleVariant: 
diff --git a/UnityProject/Assets/Scripts/VideoInput/KinectManagerBehaviour.cs b/UnityProject/Assets/Scripts/VideoInput/KinectManagerBehaviour.cs
index 90619dc..9611906 100644
--- a/UnityProject/Assets/Scripts/VideoInput/KinectManagerBehaviour.cs
+++ b/UnityProject/Assets/Scripts/VideoInput/KinectManagerBehaviour.cs
@@ -1,5 +1,6 @@
 using System;
 using System.IO;
+using System.Linq;
 using Windows.Kinect;
 using UnityEngine;
 using UnityEngine.Events;
@@ -7,7 +8,7 @@ using UnityEngine.Events;
 namespace cylvester
 {
     [Serializable] public class UnityInfraredCameraEvent : UnityEvent<Texture2D>{ }
-    [Serializable] public class UnitySkeletonEvent : UnityEvent<Body[]>{ }
+    [Serializable] public class UnitySkeletonEvent : UnityEvent<Body, int>{ }
     
     public class KinectManagerBehaviour : MonoBehaviour
     {
@@ -16,17 +17,22 @@ namespace cylvester
 
         [SerializeField] private bool skeleton;
         [SerializeField] public UnitySkeletonEvent skeletonDataReceived;
+
+        [SerializeField, Range(1, 6)] private int numberOfBodiesTobeTracked = 2;
         
         private KinectSensor sensor_;
         private InfraredFrameReader infraredFrameReader_;
         private BodyFrameReader bodyFrameReader_;
+        private BodyIndexFrameReader bodyIndexFrameReader_;
 
         private ushort [] irData_;
         private Texture2D infraredTexture_;
         private Body[] bodies_;
         
         private EventHandler<InfraredFrameArrivedEventArgs> onInfraredFrameArrived_;
-        private EventHandler<BodyFrameArrivedEventArgs> onSkeletonFrameArrived_;
+        private EventHandler<BodyFrameArrivedEventArgs> onBodyFrameArrived_;
+        private EventHandler<BodyIndexFrameArrivedEventArgs> onBodyIndexFrameArrived_;
+        private Holder<ulong> trackedIds_;
         
         private void Start()
         {
@@ -36,9 +42,11 @@ namespace cylvester
             
             InitInfraredCamera();
             InitSkeletonTracking();
-            
+
             if (!sensor_.IsOpen)
+            {
                 sensor_.Open();
+            }
         }
 
         private void InitInfraredCamera()
@@ -77,10 +85,15 @@ namespace cylvester
 
         private void InitSkeletonTracking()
         {
-            bodies_ = new Body[1];
+            bodies_ = new Body[6];
+            trackedIds_ = new Holder<ulong>(numberOfBodiesTobeTracked);
+            InitBodyFrameReader();
+        }
 
+        private void InitBodyFrameReader()
+        {
             bodyFrameReader_ = sensor_.BodyFrameSource.OpenReader();
-            onSkeletonFrameArrived_ = (frameReader, eventArgs) =>
+            onBodyFrameArrived_ = (frameReader, eventArgs) =>
             {
                 if(!skeleton)
                     return;
@@ -89,18 +102,35 @@ namespace cylvester
                 {
                     if (bodyFrame == null)
                         return;
-                    Array.Resize(ref bodies_, bodyFrame.BodyCount);
+                    
                     bodyFrame.GetAndRefreshBodyData(bodies_);
-                    skeletonDataReceived.Invoke(bodies_);
+                    foreach (var body in bodies_.Where(body => body.IsTracked))
+                    {
+                        if (trackedIds_.Exist(body.TrackingId))
+                        {
+                            var idNumber = trackedIds_.IndexOf(body.TrackingId);
+                            if(idNumber.HasValue)
+                                skeletonDataReceived.Invoke(body, idNumber.Value);
+                        }
+                        else
+                        {
+                            if (trackedIds_.Add(body.TrackingId))
+                            {
+                                var idNumber = trackedIds_.IndexOf(body.TrackingId);
+                                if (idNumber.HasValue) 
+                                    skeletonDataReceived.Invoke(body, idNumber.Value);
+                            }
+                        }
+                    }
                 }
             };
-            bodyFrameReader_.FrameArrived += onSkeletonFrameArrived_;
+            bodyFrameReader_.FrameArrived += onBodyFrameArrived_;
         }
-
+        
         private void OnDestroy()
         {
             infraredFrameReader_.FrameArrived -= onInfraredFrameArrived_;
-            bodyFrameReader_.FrameArrived -= onSkeletonFrameArrived_;
+            bodyFrameReader_.FrameArrived -= onBodyFrameArrived_;
         }
     }
 }