Outsourcing a business practice to another company may also be incorporated into a sourcing strategy for services. This strategy may involve the transfer of staff and assets to the outsource company. Due to the strategic and complex nature of outsourcing, many organizations such as Procter & Gamble, Microsoft and McDonald's have created what is referred to as Vested Outsourcing agreements to help build highly collaborative win-win business relationships. Researchers at the University of Tennessee provide guidance on how to create Vested Outsourcing agreements in their book Vested Outsourcing: Five Rules that will Transform Outsourcing.