Division of labour has played a very important role in the evolution of complexity: with many individuals working towards a common goal, great feats can be accomplished. One of the most extreme examples of division of labour is demonstrated by eusocial insects which are divided into reproductives and non-reproductives. The forfeiting of ones own reproductive potential may seem evolutionarily counterintuitive but can be explained by kin selection: helping close relatives to reproduce helps an individual to pass on their genes to the next generation indirectly. I will be exploring the evolution of sociality across insect taxa to try to answer why it has evolved independently a number of times, but only in certain branches of the tree of life.