Application development and delivery (AD&D) leaders need strong partnerships with a few key software providers, due to the risk of vendor lock-in, particularly with SaaS platforms and the need for external ideas and innovative thinking. Yet few supplier relationships actually deserve the "strategic partner" title. This report explains how to build and nurture strong, long-lasting relationships with your most important technology suppliers. This is an update of an earlier report that we published in July 2015. It includes new examples, fresh data, and revised recommendations.