Most of us would like something about ourselves or our lives to be different, but how easy is it to actually change?

Drs Chris and Xand van Tulleken are looking at whether people can change and how they do it. Exactly how much of any aspect of personality is genetic destiny and how much are we shaped by the world around us?

Chris wants to be a better doctor, friend, husband and father. But most urgently he wants to be a better brother, and is determined to improve his relationship with Xand. They’re best friends and talk to each other every day, but they are also business partners who find it very hard to work together without having a visceral row.

Chris wants to change how he relates to his brother and believes it is possible, but Xand is less convinced that we can or that he needs to change. In this series, Chris confronts that pessimism.

In episode 8 - Changing Our Environment - Xand convinces Chris to come into his pottery shed and give it a whirl. Working together has historically resulted in heated arguments, so it’s time for Chris to act on what he’s learnt about improving his relationship with Xand. The twins consider how easy it is to roll out change on a large scale and ask Will Norman how he manages to implement change in the face of opposition.

Presented by Drs Chris and Xand van Tulleken Produced by Hester Cant and Alexandra Quinn Series Editor: Jo Rowntree A Loftus Media and van Tulleken Brothers Ltd production for BBC Radio 4