In his book "The Best of Times: America In The Clinton Years", Pulitzer Prize-winning journalist Haynes Johnson sums up the 1990s as an era of peace, prosperity, scandal, and missed opportunities. It was a time of unprecedented wealth; revolutions were taking place in technology with the world-changing Internet, and in medicine with the mapping of the human genome. However, there was another America dominated by a media filled with scandal and celebrity. 9/11 was definitely a catalyst for change. (Originally aired November 2001)

Pulitzer Prize-winning science writer Natalie Angier, is the author of "Woman: An Intimate Geography", which is an investigation of female physiology and an explanation of how biology affects us as who we are. (Originally aired June 1999)

John Colapinto is the author of "As Nature Made Him: The Boy Who Was Raised as a Girl." The book recounts the tragic story of David Reimer of Manitoba, an identical twin boy who was raised as a girl after a tragic accident to his genitalia. Sadly David Reimer committed suicide in May 2004. (Originally aired March 2000)

David Shenk is the author of "The Forgetting: Alzheimer's, Portrait of an Epidemic". Shenk talks about this insidious disease, which, because of an ageing population, seems to be reaching epidemic proportions. There is still no known cause or cure although some drugs can mask some symptoms experienced in the early part of the disease. (Originally aired: November 2001)

Neurosurgeon and CNN medical correspondent Dr. Sanjay Gupta has written a novel, "Monday Mornings". The title refers to the closed-door morbidity and mortality meetings which doctors attend on Monday mornings, to discuss medical errors. Dr. Gupta also talks about being embedded with troops in Iraq in 2003, and performing brain surgery in the field. On the topic of healthcare in the U.S., he believes more should be done to prevent rather than treat diseases. He thinks it is possible to eradicate heart disease.

Rachel Simmons is the author of "Odd Girl Out: The Hidden Culture of Aggression in Girls". Whereas boys' aggression often takes a physical form, girls will be more subtle, using manipulation and name-calling or threatening isolation from their peers. (Originally aired October 2002)

In his new book "The End of Growth", economist Jeffrey Rubin says that the end of cheap oil will mean the end of growth. He explains the impact high oil prices have on the economy as they cause higher inflation and interest rates, thereby pushing the country into a recession.

Pulitzer Prize-winning author Timothy Ferris, talks about his latest book, "The Whole Shebang", which is about the state of the universe. (Original show aired June 1997)

In his new book, "Champlain's Dream", Pulitzer Prize-winning American historian David Hackett Fischer, brings to life a giant of Canadian history, explorer Samuel de Champlain. (Originally aired April 2009)

Head of the University of Toronto's Rotman School of Management, Roger Martin talks about his book "Fixing the Game". He says it's time to overhaul the corporate world and to stop believing that corporations exist only to maximize shareholder value. Businesses should go back to being customer-based.