“Sieve analysis could be seen as the low grade workhorse of particle sizing, yet it is a widely used system as sieves are commonplace worldwide. However, with strict quality assurance demands, it needs to be more accurate to suit the demands of today’s researchers. Methods of sieve calibration include microscopy – which has its limitations – and sieve calibration microspheres. This article describes how the use of narrow particle size distribution standards has enabled sieve calibration to be brought into the laboratory, meeting the need for routine inspection by regulatory bodies.” Sue Fakes ILM Feature Editor