As hardening competition in industry pushes manufacturing companies to deliver increased customer value, communication with the customer during the use-phase becomes paramount. This paper investigates whether warranty management could be a method for improved integrated product/service engineering (IPSE) as a firm moves from component to system solution supplier. The research methodology applied was a multiple case study, with four suppliers as focal firms, where buyer-supplier relationships were investigated from a supplier perspective. Results show that advanced warranty reporting, implemented as a strategic tool, can be a key to efficient IPSE.