Louis Tay is the William C. Byham Professor of Industrial-Organizational Psychology at Purdue University. His substantive research interests include well-being (subjective well-being, psychological well-being), character strengths, and vocational interests. His methodological research interests include measurement, item response theory, latent class modeling, multilevel analysis, and data science. He is a co-editor of the books Big Data in Psychological Research (APA Books) and Handbook of Well-Being (DEF Publishers). He has contributed to the United Nations’ research reports on well-being and serves in consulting roles to top tech companies and Fortune 500 organizations. Consultations have involved topics such as better understanding customer and employee well-being, improving recruitment and selection processes, and understanding biases in measurement, machine learning, and AI. He is the founder of the tech-startup ExpiWell (www.expiwell.com) that advances the science and capture of daily life experiences through experience sampling methodology.