PopupLookup control, an alternative for AJAX?

using System;

namespace Business
{
    [System.ComponentModel.DataObject]
    public class Organisation : IBusiness
    {
        [System.ComponentModel.DataObjectMethod(System.ComponentModel.DataObjectMethodType.Select, true)]
        public LookupDataSet GetLookupList(string partOfNaam)
        {
            LookupDataSet ds = new LookupDataSet();

            for (int i = 0; i < 10; i++)
            {
                ds.Lookup.AddLookupRow(string.Format("OrganisationName{0}", i), i, string.Format("OrganisationDescription {0}", i));
            }

            return ds;
        }

        public string Name()
        {
            return this.GetType().Name;
        }
    }
}