Automated decision technology (ADT) has become pervasive in the mortgage lending industry. The authors of this article have been at the cutting edge of mission-critical ADT in the mortgage industry over the past decade. The design and implementation process for ADT systems differs enough from conventional software projects that companies cannot safely assume that their past successes in planning and managing information technology (IT) projects will be transferable to ADT projects. The good news is that with proper training and forethought, companies can significantly improve their ability to plan and execute ADT projects. This article describes many of the pitfalls that companies commonly face and identifies best practices for preventing these problems from derailing ADT initiatives. The article is segmented into six major topic areas describing pitfalls common in each. These are: 1. organizational planning, 2. budgeting and timeline planning, 3. knowledge engineering, 4. presenting the decision (user interfaces), 5. validation and testing, and 6. building or buying.