Data-based decision making has always been a fundamental part of banking and finance. This has become even more so after the 2008 crisis and the heightened regulatory environment. In this presentation, I will describe the role of statistics in risk modeling and management in large banks, covering model development and model assessment. The talk will give a glimpse into different types of data structures, computing/data platforms used for big data, types of models, and how they are developed and used. I will also describe a couple of specific examples of applied research problems dealing with multi-state transition modeling and data validation.