As Christmas approaches, many of us will have spent the last few weeks trying to pick out the perfect presents for friends, family and colleagues. For both giver and receiver, exchanging gifts can be filled with delight – or dread, as a smile slowly fades into a look of feigned enthusiasm. But what does science say about how to avoid unwanted gifts and unpleasant surprises? Ian Sample speaks to Julian Givi about his research unwrapping what we all actually want under the tree, and hears his top tips for choosing a winning present every time. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>