What happens to a man’s fertility as he ages? What genetic changes occur in sperm as men age? Should older men who want to be fathers be worried about the health of their offspring? We have never thought about this before, so why now? It’s only been the last 100 years in the history of mankind that we have been living long enough to even think about advanced paternal age issues. Given the fact the age at fatherhood has risen consistently over the last 2 generations, these questions are real and merit discussion.