This chapter presents an overview of Resilient Health Care (RHC), introducing two aspects of RHC that are important for designing sustainable digital health systems and for considering implementation outcomes: (1) understanding how normal variation in everyday work can affect implementation of digital health interventions, and (2) the role of information systems in coping with unexpected events. The importance of considering how variation in everyday work can lead to wanted and unwanted outcomes when designing information systems is illustrated through a case study of implementation of a telehealth intervention. We examine how normal variation in everyday work can lead to both safety and error, and discuss how consideration of system resilience when designing and implementing health informatics applications can contribute to improving safety for patients in the future. How health information systems can assist organisations in coping with the unexpected is illustrated through a second case study, of a thunderstorm asthma event in Melbourne, Australia. We briefly present the thunderstorm asthma case, and discuss the role of healthcare informatics in preparing for future unexpected events affecting population health.