This report is the IPEM publication on quality assurance of ultrasound imaging systems. The purpose of the report is twofold, firstly to provide a group of robust simple tests which can be performed quickly by the user for regular checking of a clinical ultrasound scanner. Secondly, it provides guidance to ultrasound professionals for performing complex testing appropriate to acceptance or queries relating to system performance. The first four chapters cover the introduction and background, followed by guidance for B-mode, Doppler and safety measurements. The final chapter is intended to inform and hopefully inspire research in to methodologies for measuring the performance of increasingly complex ultrasound imaging systems. The publication is aimed at all users of ultrasound imaging systems but will be of particular use to clinical scientists responsible for the acceptance and ongoing support of such systems. A number of appendices provide information on the testing equipment needed to perform the specialist tests. All of the user tests can be performed with no special equipment.