Professor Chris Stringer, Research Leader in Human Origins at the Natural History Museum, London, gave the 2015 Haldane Lecture at Wolfson College, Oxford. He discusses how we are mostly, but not entirely, 'Out of Africa'. Human Evolution can be divided into two main phases. A pre-human phase in Africa prior to 2 million years ago, where walking upright had evolved but some other characteristics were still ape-like. And a human phase, with an increase in both brain size and behavioural complexity, and an expansion from Africa. Evidence points strongly to Africa as the major centre for the genetic, physical and behavioural origins of both ancient and modern humans, but new discoveries are prompting a rethink of some aspects of our evolutionary origins, including the likelihood of interbreeding between archaic humans (for example the Neanderthals) and modern humans. We are mostly, but not entirely, 'Out of Africa'. Chris Stringer first worked at the Natural HistoryMuseum in 1969-1970, but joined the permanent staff in 1973, where he is now a Research Leader in Human Origins. His early research was on the relationship of Neanderthals and early modern humans in Europe, but through his work on the Recent African Origin model for modern human origins, he now collaborates with archaeologists, dating specialists, and geneticists in attempting to reconstruct the evolution of modern humans globally. He's excavated at sites in Britain and abroad, and directed the Ancient Human Occupation of Britain project from 2001 until it finished in 2013. Now co-director of the follow-up Pathways to Ancient Britain project. Those projects led to the successful Britain: One Million Years of the Human Story exhibition in 2014. As well as many scientific papers, He's also written a number of books, most recently The Origin of Our Species (2012, published in the USA as Lone Survivors: how we came to be the only humans on Earth), and Britain: one million years of the human story (2014, with Rob Dinnis). Creative Commons Attribution-Non-Commercial-Share Alike 2.0 UK: England & Wales; http://creativecommons.org/licenses/by-nc-sa/2.0/uk/