Here are the relevant facts: In 1996, Hershey's set out to upgrade its patchwork of legacy IT systems into an integrated ERP environment. It chose SAP's R/3 ERP software, Manugistic's supply chain management (SCM) software and Seibel's customer relationship management (CRM) software. Despite a recommended implementation time of 48 months, Hershey's demanded a 30-month turnaround so that it could roll out the systems before Y2K. Based on these scheduling demands, cutover was planned for July of 1999. This go-live scheduling coincided with Hershey's busiest periods - the time during which it would receive the bulk of its Halloween and Christmas orders. To meet the aggressive scheduling demands, Hershey's implementation team had to cut corners on critical systems testing phases. When the systems went live in July of 1999, unforeseen issues prevented orders from flowing through the systems. As a result, Hershey's was incapable of processing $100 million worth of Kiss and Jolly Rancher orders, even though it had most of the inventory in stock. This is not one of those "hindsight is 20-20" cases. A reasonably prudent implementer in Hershey's position would never have permitted cutover under those circumstances. The risks of failure and exposure to damages were simply too great. Unfortunately, too few companies have learned from Hershey's mistakes. For our firm, it feels like Groundhog Day every time we are retained to rescue a failed or failing ERP project. In an effort to help companies implement ERP correctly - the first time - I have decided to rehash this old Hershey's case. The two key lessons I describe below relate to systems testing and project scheduling.