(Presented in Denver, Colorado, on Nov 15, 2013, at CHIMSS.org's Fall Half Day Educational Program in conjunction with World Usability Day: “Raising Awareness and Promoting Usability Best Practices in Health Organizations World-Wide”) Summary: Usability as a concept originates in the era, not long ago, when we were so impressed by what information technology could do for us that we accepted difficult user interfaces as unfortunate but inevitable facts of life. Our main interest was in functionality. In 2005, World Usability Day was created to spread awareness of the benefits of designing technology that not only performs useful functions, but also interacts well with human users – including those without technical expertise. The initial focus of usability was simply on giving ordinary people the ability to use technology without needing expensive and time-consuming training. However, ability to use is really just the tip of the iceberg. The iceberg here is the inescapable humanness of information technology. IT is created by humans, interacts with humans, and has both positive and negative impacts on humans. Below the tip of the iceberg lie human impacts that are deeper, but less obvious, than ability to use. They include impacts on stress, emotion, thinking, decision-making, and social interaction. The best doctors not only diagnose conditions and prescribe treatments, but also interact with their patients in ways that actively support healing – for example by building trust, expressing care, and supporting resilience. Similarly, the best healthcare information technology not only delivers functionality, but also interacts with its users in ways that actively support positive psychological processes – for example, by helping people to manage stress and emotion, think clearly and make good decisions, and treat each other well.