Populations can be divided into generations. Each generation has its own characteristics and even though not every member of the same generation will share characteristics with other members of that generation, it is possible to identify generational differences. Generations frequently have different values and varying styles of functioning and learning. Since the Second World War, the generations can be divided into four cohorts: the Veterans, the Baby Boomers, Generation X, and the Millennials. Each generation has a collective identity and, in addition to understanding cultural and ethnic differences, these generational differences should also be taken into account in the teaching arena. Values and beliefs about work-life balance, learning styles, comfort with technology, methods of communication, and approaches to leadership are the types of parameters which vary across generations. As a result, medical educators would benefit from appreciating these differences in order to enhance the learning of medical students and residents and to better prepare them for delivering patient care in the twenty-first century. In this paper, the authors highlight some of the challenges and issues related to these generational divides. (C) 2011 Elsevier B.V. All rights reserved.