diff --git a/src/LEGO.AsyncAPI/Models/AsyncApiAvroSchemaPayload.cs b/src/LEGO.AsyncAPI/Models/AsyncApiAvroSchemaPayload.cs
index 786d9cd3..141916d7 100644
--- a/src/LEGO.AsyncAPI/Models/AsyncApiAvroSchemaPayload.cs
+++ b/src/LEGO.AsyncAPI/Models/AsyncApiAvroSchemaPayload.cs
@@ -10,11 +10,6 @@ public class AsyncApiAvroSchemaPayload : IAsyncApiMessagePayload
     {
         private AvroSchema schema;
 
-        public AsyncApiAvroSchemaPayload()
-        {
-            this.schema = new AvroSchema();
-        }
-
         public AsyncApiAvroSchemaPayload(AvroSchema schema)
         {
             this.schema = schema;
diff --git a/src/LEGO.AsyncAPI/Models/Avro/AvroArray.cs b/src/LEGO.AsyncAPI/Models/Avro/AvroArray.cs
index 65f2cddd..9306c7d9 100644
--- a/src/LEGO.AsyncAPI/Models/Avro/AvroArray.cs
+++ b/src/LEGO.AsyncAPI/Models/Avro/AvroArray.cs
@@ -2,6 +2,8 @@
 
 namespace LEGO.AsyncAPI.Models
 {
+    using System.Collections.Generic;
+    using System.Linq;
     using LEGO.AsyncAPI.Writers;
 
     public class AvroArray : AvroSchema
@@ -10,11 +12,31 @@ public class AvroArray : AvroSchema
 
         public AvroSchema Items { get; set; }
 
+        /// <summary>
+        /// A map of properties not in the schema, but added as additional metadata.
+        /// </summary>
+        public IDictionary<string, AvroSchema> Metadata { get; set; } = new Dictionary<string, AvroSchema>();
+
         public override void SerializeV2(IAsyncApiWriter writer)
         {
             writer.WriteStartObject();
             writer.WriteOptionalProperty("type", this.Type);
             writer.WriteRequiredObject("items", this.Items, (w, f) => f.SerializeV2(w));
+            if (this.Metadata.Any())
+            {
+                foreach (var item in this.Metadata)
+                {
+                    writer.WritePropertyName(item.Key);
+                    if (item.Value == null)
+                    {
+                        writer.WriteNull();
+                    }
+                    else
+                    {
+                        item.Value.SerializeV2(writer);
+                    }
+                }
+            }
             writer.WriteEndObject();
         }
     }
diff --git a/src/LEGO.AsyncAPI/Models/Avro/AvroEnum.cs b/src/LEGO.AsyncAPI/Models/Avro/AvroEnum.cs
index ae474e4f..92b02ad3 100644
--- a/src/LEGO.AsyncAPI/Models/Avro/AvroEnum.cs
+++ b/src/LEGO.AsyncAPI/Models/Avro/AvroEnum.cs
@@ -3,6 +3,7 @@
 namespace LEGO.AsyncAPI.Models
 {
     using System.Collections.Generic;
+    using System.Linq;
     using LEGO.AsyncAPI.Writers;
 
     public class AvroEnum : AvroSchema
@@ -10,7 +11,7 @@ public class AvroEnum : AvroSchema
         public string Type { get; } = "enum";
 
         public string Name { get; set; }
-        
+
         public string Namespace { get; set; }
 
         public string Doc { get; set; }
@@ -21,16 +22,36 @@ public class AvroEnum : AvroSchema
 
         public string Default { get; set; }
 
+        /// <summary>
+        /// A map of properties not in the schema, but added as additional metadata.
+        /// </summary>
+        public IDictionary<string, AvroSchema> Metadata { get; set; } = new Dictionary<string, AvroSchema>();
+
         public override void SerializeV2(IAsyncApiWriter writer)
         {
             writer.WriteStartObject();
             writer.WriteOptionalProperty("type", this.Type);
             writer.WriteRequiredProperty("name", this.Name);
-            writer.WriteRequiredProperty("namespace", this.Namespace);
+            writer.WriteOptionalProperty("namespace", this.Namespace);
             writer.WriteOptionalCollection("aliases", this.Aliases, (w, s) => w.WriteValue(s));
             writer.WriteOptionalProperty("doc", this.Doc);
             writer.WriteRequiredCollection("symbols", this.Symbols, (w, s) => w.WriteValue(s));
             writer.WriteRequiredProperty("default", this.Default);
+            if (this.Metadata.Any())
+            {
+                foreach (var item in this.Metadata)
+                {
+                    writer.WritePropertyName(item.Key);
+                    if (item.Value == null)
+                    {
+                        writer.WriteNull();
+                    }
+                    else
+                    {
+                        item.Value.SerializeV2(writer);
+                    }
+                }
+            }
             writer.WriteEndObject();
         }
     }
diff --git a/src/LEGO.AsyncAPI/Models/Avro/AvroField.cs b/src/LEGO.AsyncAPI/Models/Avro/AvroField.cs
index 89be453b..5ce87047 100644
--- a/src/LEGO.AsyncAPI/Models/Avro/AvroField.cs
+++ b/src/LEGO.AsyncAPI/Models/Avro/AvroField.cs
@@ -5,6 +5,7 @@ namespace LEGO.AsyncAPI.Models
     using LEGO.AsyncAPI.Models.Interfaces;
     using LEGO.AsyncAPI.Writers;
     using System.Collections.Generic;
+    using System.Linq;
 
     /// <summary>
     /// Represents a field within an Avro record schema.
@@ -41,6 +42,11 @@ public class AvroField : IAsyncApiSerializable
         /// </summary>
         public IList<string> Aliases { get; set; } = new List<string>();
 
+        /// <summary>
+        /// A map of properties not in the schema, but added as additional metadata.
+        /// </summary>
+        public IDictionary<string, AvroSchema> Metadata { get; set; } = new Dictionary<string, AvroSchema>();
+
         public void SerializeV2(IAsyncApiWriter writer)
         {
             writer.WriteStartObject();
@@ -50,6 +56,21 @@ public void SerializeV2(IAsyncApiWriter writer)
             writer.WriteOptionalObject("default", this.Default, (w, s) => w.WriteAny(s));
             writer.WriteOptionalProperty("order", this.Order);
             writer.WriteOptionalCollection("aliases", this.Aliases, (w, s) => w.WriteValue(s));
+            if (this.Metadata.Any())
+            {
+                foreach (var item in this.Metadata)
+                {
+                    writer.WritePropertyName(item.Key);
+                    if (item.Value == null)
+                    {
+                        writer.WriteNull();
+                    }
+                    else
+                    {
+                        item.Value.SerializeV2(writer);
+                    }
+                }
+            }
             writer.WriteEndObject();
         }
     }
diff --git a/src/LEGO.AsyncAPI/Models/Avro/AvroFixed.cs b/src/LEGO.AsyncAPI/Models/Avro/AvroFixed.cs
index 35363425..d7bac5de 100644
--- a/src/LEGO.AsyncAPI/Models/Avro/AvroFixed.cs
+++ b/src/LEGO.AsyncAPI/Models/Avro/AvroFixed.cs
@@ -4,26 +4,48 @@ namespace LEGO.AsyncAPI.Models
 {
     using LEGO.AsyncAPI.Writers;
     using System.Collections.Generic;
+    using System.Linq;
 
     public class AvroFixed : AvroSchema
     {
         public string Type { get; } = "fixed";
 
         public string Name { get; set; }
-        public string Namespaace { get; set; }
+
+        public string? Namespaace { get; set; }
 
         public IList<string> Aliases { get; set; } = new List<string>();
 
         public int Size { get; set; }
 
+        /// <summary>
+        /// A map of properties not in the schema, but added as additional metadata.
+        /// </summary>
+        public IDictionary<string, AvroSchema> Metadata { get; set; } = new Dictionary<string, AvroSchema>();
+
         public override void SerializeV2(IAsyncApiWriter writer)
         {
             writer.WriteStartObject();
             writer.WriteOptionalProperty("type", this.Type);
             writer.WriteRequiredProperty("name", this.Name);
-            writer.WriteRequiredProperty("name", this.Namespaace);
+            writer.WriteOptionalProperty("namespace", this.Namespaace);
             writer.WriteOptionalCollection("aliases", this.Aliases, (w, s) => w.WriteValue(s));
             writer.WriteRequiredProperty("size", this.Size);
+            if (this.Metadata.Any())
+            {
+                foreach (var item in this.Metadata)
+                {
+                    writer.WritePropertyName(item.Key);
+                    if (item.Value == null)
+                    {
+                        writer.WriteNull();
+                    }
+                    else
+                    {
+                        item.Value.SerializeV2(writer);
+                    }
+                }
+            }
             writer.WriteEndObject();
         }
     }
diff --git a/src/LEGO.AsyncAPI/Models/Avro/AvroMap.cs b/src/LEGO.AsyncAPI/Models/Avro/AvroMap.cs
index fa99615d..382f25d5 100644
--- a/src/LEGO.AsyncAPI/Models/Avro/AvroMap.cs
+++ b/src/LEGO.AsyncAPI/Models/Avro/AvroMap.cs
@@ -4,20 +4,40 @@ namespace LEGO.AsyncAPI.Models
 {
     using System;
     using System.Collections.Generic;
+    using System.Linq;
     using LEGO.AsyncAPI.Writers;
 
     public class AvroMap : AvroSchema
     {
         public string Type { get; } = "map";
 
-        public IDictionary<string, string> Values { get; set; } = new Dictionary<string, string>();
+        public AvroPrimitiveType Values { get; set; }
+
+        /// <summary>
+        /// A map of properties not in the schema, but added as additional metadata.
+        /// </summary>
+        public IDictionary<string, AvroSchema> Metadata { get; set; } = new Dictionary<string, AvroSchema>();
 
         public override void SerializeV2(IAsyncApiWriter writer)
         {
-            Convert.ToBoolean()
             writer.WriteStartObject();
             writer.WriteOptionalProperty("type", this.Type);
-            writer.WriteRequiredObject("values", this.Values, (w, f) => f.SerializeV2(w));
+            writer.WriteRequiredProperty("values", this.Values.GetDisplayName());
+            if (this.Metadata.Any())
+            {
+                foreach (var item in this.Metadata)
+                {
+                    writer.WritePropertyName(item.Key);
+                    if (item.Value == null)
+                    {
+                        writer.WriteNull();
+                    }
+                    else
+                    {
+                        item.Value.SerializeV2(writer);
+                    }
+                }
+            }
             writer.WriteEndObject();
         }
     }
diff --git a/src/LEGO.AsyncAPI/Models/Avro/AvroPrimitive.cs b/src/LEGO.AsyncAPI/Models/Avro/AvroPrimitive.cs
index 7025a31d..6810f1e2 100644
--- a/src/LEGO.AsyncAPI/Models/Avro/AvroPrimitive.cs
+++ b/src/LEGO.AsyncAPI/Models/Avro/AvroPrimitive.cs
@@ -2,20 +2,46 @@
 
 namespace LEGO.AsyncAPI.Models
 {
+    using System.Collections.Generic;
+    using System.Linq;
     using LEGO.AsyncAPI.Writers;
 
     public class AvroPrimitive : AvroSchema
     {
         public AvroPrimitiveType Type { get; set; }
 
+        /// <summary>
+        /// A map of properties not in the schema, but added as additional metadata.
+        /// </summary>
+        public IDictionary<string, AvroSchema> Metadata { get; set; } = new Dictionary<string, AvroSchema>();
+
         public AvroPrimitive(AvroPrimitiveType type)
         {
             this.Type = type;
         }
 
+        public AvroPrimitive()
+        {
+        }
+
         public override void SerializeV2(IAsyncApiWriter writer)
         {
             writer.WriteValue(this.Type.GetDisplayName());
+            if (this.Metadata.Any())
+            {
+                foreach (var item in this.Metadata)
+                {
+                    writer.WritePropertyName(item.Key);
+                    if (item.Value == null)
+                    {
+                        writer.WriteNull();
+                    }
+                    else
+                    {
+                        item.Value.SerializeV2(writer);
+                    }
+                }
+            }
         }
     }
 }
\ No newline at end of file
diff --git a/src/LEGO.AsyncAPI/Models/Avro/AvroRecord.cs b/src/LEGO.AsyncAPI/Models/Avro/AvroRecord.cs
index c45936f6..c5725dd4 100644
--- a/src/LEGO.AsyncAPI/Models/Avro/AvroRecord.cs
+++ b/src/LEGO.AsyncAPI/Models/Avro/AvroRecord.cs
@@ -25,18 +25,27 @@ public class AvroRecord : AvroSchema
         /// </summary>
         public string? Doc { get; set; }
 
+        /// <summary>
+        /// 
+        /// </summary>
         public IList<string> Aliases { get; set; } = new List<string>();
 
+        /// <summary>
+        /// 
+        /// </summary>
         public IList<AvroField> Fields { get; set; } = new List<AvroField>();
 
-        public IDictionary<string, AvroFieldType> Metadata { get; set; } = new Dictionary<string, AvroFieldType>();
+        /// <summary>
+        /// A map of properties not in the schema, but added as additional metadata.
+        /// </summary>
+        public IDictionary<string, AvroSchema> Metadata { get; set; } = new Dictionary<string, AvroSchema>();
 
         public override void SerializeV2(IAsyncApiWriter writer)
         {
             writer.WriteStartObject();
             writer.WriteOptionalProperty("type", this.Type);
             writer.WriteRequiredProperty("name", this.Name);
-            writer.WriteRequiredProperty("namespace", this.Namespace);
+            writer.WriteOptionalProperty("namespace", this.Namespace);
             writer.WriteOptionalProperty("doc", this.Doc);
             writer.WriteOptionalCollection("aliases", this.Aliases, (w, s) => w.WriteValue(s));
             writer.WriteRequiredCollection("fields", this.Fields, (w, s) => s.SerializeV2(w));
diff --git a/src/LEGO.AsyncAPI/Models/Avro/AvroUnion.cs b/src/LEGO.AsyncAPI/Models/Avro/AvroUnion.cs
index 7949dd4a..567a5dd6 100644
--- a/src/LEGO.AsyncAPI/Models/Avro/AvroUnion.cs
+++ b/src/LEGO.AsyncAPI/Models/Avro/AvroUnion.cs
@@ -3,12 +3,18 @@
 namespace LEGO.AsyncAPI.Models
 {
     using System.Collections.Generic;
+    using System.Linq;
     using LEGO.AsyncAPI.Writers;
 
     public class AvroUnion : AvroSchema
     {
         public IList<AvroSchema> Types { get; set; } = new List<AvroSchema>();
 
+        /// <summary>
+        /// A map of properties not in the schema, but added as additional metadata.
+        /// </summary>
+        public IDictionary<string, AvroSchema> Metadata { get; set; } = new Dictionary<string, AvroSchema>();
+
         public override void SerializeV2(IAsyncApiWriter writer)
         {
             writer.WriteStartArray();
@@ -16,6 +22,22 @@ public override void SerializeV2(IAsyncApiWriter writer)
             {
                 type.SerializeV2(writer);
             }
+
+            if (this.Metadata.Any())
+            {
+                foreach (var item in this.Metadata)
+                {
+                    writer.WritePropertyName(item.Key);
+                    if (item.Value == null)
+                    {
+                        writer.WriteNull();
+                    }
+                    else
+                    {
+                        item.Value.SerializeV2(writer);
+                    }
+                }
+            }
             writer.WriteEndArray();
         }
     }