The problem: I have a custom collection PagedList<T> that is being returned from my WCF service as PagedListOfEntitySearchResultW_SH0Zpu5 when T is EntitySearchResult object. I want to reuse this PagedList<T> type between the application and the service. My scenario: I've created a PagedList<T> type that inherits from List<T>. This type is on a separated assembly that is referenced on both application and WCF service. I'm using the /reference option on the scvutil to enable the type reusing. I also don't want any arrays returned so I also use the /collection to map to the generic List type. I'm using the following svcutil command to generate the service proxy: "C:\Program Files (x86)\Microsoft SDKs\Windows\v7.0A\Bin\NETFX 4.0 Tools\svcutil.exe" /collectionType:System.Collections.Generic.List`1 /reference:..\..\bin\Debug\App.Utilities.dll http://localhost/App.MyService/MyService.svc?wsdl /namespace:*,"App.ServiceReferences.MyService" /out:..\ServiceProxy\MyService.cs The PagedList object is something like: [CollectionDataContract] public partial class PagedList<T> : List<T> { public PagedList() { } /// <summary> /// Creates a new instance of the PagedList object and doesn't apply any pagination algorithm. /// The only calculated property is the TotalPages, everything else needed must be passed to the object. /// </summary> /// <param name="source"></param> /// <param name="pageNumber"></param> /// <param name="pageSize"></param> /// <param name="totalRecords"></param> public PagedList(IEnumerable<T> source, int pageNumber, int pageSize, int totalRecords) { if (source == null) source = new List<T>(); this.AddRange(source); PagingInfo.PageNumber = pageNumber; PageSize = pageSize; TotalRecords = totalRecords; } public PagedList(IEnumerable<T> source, PagingInfo paging) { this.AddRange(source); this._pagingInfo = paging; } [DataMember] public int TotalRecords { get; set; } [DataMember] public int PageSize { get; set; } public int TotalPages() { if (this.TotalRecords > 0 && PageSize > 0) return (int)Math.Ceiling((double)TotalRecords / (double)PageSize); else return 0; } public bool? HasPreviousPage() { return (PagingInfo.PageNumber > 1); } public bool? HasNextPage() { return (PagingInfo.PageNumber < TotalPages()); } public bool? IsFirstPage() { return PagingInfo.PageNumber == 1; } public bool? IsLastPage() { return PagingInfo.PageNumber == TotalPages(); } PagingInfo _pagingInfo = null; [DataMember] public PagingInfo PagingInfo { get { if (_pagingInfo == null) _pagingInfo = new PagingInfo(); return _pagingInfo; } set { _pagingInfo = value; } } }