Here is a brief history of the work of two of Australia's most famous scientists, Sir William Bragg and his son Sir Lawrence Bragg. Jointly awarded the Nobel Prize in 1915 for their groundbreaking research into the use of X-rays to study the chemical structure and function of molecules, they have contributed to our heritage and to science at an international level. In this, the Year of Crystallography, it is fitting to look at the Braggs whose X-ray work was an important step in the development of X-ray crystallography.