This short 3-day or 5-day on-line course will provide training in the design, conduct and analysis of cluster randomized trials (CRTs) and stepped-wedge cluster randomized trials (SW-CRTs). Delivered by faculty of the University of Birmingham including Karla Hemming, Sam Watson and James Martin. With guest speaker Anges Caille (INSERM, France) who will give an overview of the bias issues raised by cluster randomised trials.