public class Party : Entity
   {
      private Address address;
      private string telephone;
      private string email;

      #region Constructors
      public Party() : this(null)
      {
      }

      public Party(string name) : this(name, null)
      {
      }

      public Party(string name, string telephone) : this(name, telephone, null)
      {
      }

      public Party(string name, string telephone, string email) : base(name)
      {
         address = new Address();
         Telephone = telephone;
         Email = email;
      }
      #endregion

      /// <summary>
      /// Property Address (Address)
      /// </summary>
      public Address Address
      {
         get   { return address; }
         set { address = value; }
      }

      public string Telephone
      {
         get { return telephone; }
         set { telephone = value; }
      }

      public string Email
      {
         get { return email; }
         set { email = value; }
      }
   }

<hibernate-mapping xmlns="urn:nhibernate-mapping-2.0" namespace="Lbth.Sar.Domain" assembly="Lbth.Sar.Domain" default-access="field.camelcase">
   <subclass name="Party" extends="Entity" discriminator-value="Party">
      <property name="Email" column="Email" type="String" />
      <property name="Telephone" column="Telephone" type="String" />
      <component name="Address" class="Address">
         <property name="Street" column="Street" type="String" />
         <property name="City" column="City" type="String" />
         <property name="Postcode" column="Postcode" type="String" />
         <property name="County" column="County" type="String" />
      </component>
   </subclass>
</hibernate-mapping>