The National Science + Engineering Competition began in 2008 following a suggestion from Lord Sainsbury while he was Chief Scientist Advisor to the government.

The aim of the Competition is to recognise and reward young people’s achievements in all areas of Science, Technology, Engineering and Mathematics (STEM) and by doing so, encourage others to engage with STEM and consider STEM-related career paths. The Competition's finals are held annually at The Big Bang Fair where each finalist displays and demonstrates their project work to visiting school groups and the wider public. By seeing the achievements of their peers, it is hoped that students visiting the fair will be encouraged to engage with STEM themselves.

The British Science Association coordinates the National Science + Engineering Competition in partnership with The Big Bang Fair and Young Engineers. The Competition is funded by the Department for Business, Innovation and Skills (BIS). A number of institutions and organisations also provide specific additional prizes for Competition winners.