Varicoceles are relatively common particularly in asymptomatic men and are even more prevalent in subfertile men, representing the most common potentially correctable cause of male infertility. Ultrasound (US) is the imaging modality of choice for varicocele evaluation, but there is no widely accepted consensus on examination technique, diagnostic criteria, or classification. In view of this uncertainty, the guideline writing group (WG) of the European Society of Urogenital Radiology (ESUR) Scrotal and Penile Imaging Working Group (ESUR-SPIWG) undertook a literature review and assessment of the quality of relevant evidence. The group then produced evidence-based recommendations for varicocele US examination, interpretation, and classification by consensus agreement. The results are presented in the form of 15 clinical questions with a brief summary of the relevant evidence and the authorised recommendations from the SPIWG. This paper provides a short summary of the evidence evaluation and the complete recommendations. Key Points • Varicocele is a common clinical problem; it is highly prevalent amongst subfertile men and the most common potentially correctable cause of male infertility. • Ultrasound is the imaging modality of choice for varicocele assessment, but there is no generally agreed consensus on the US examination technique or the criteria that should be used for diagnosis, grading, and classification. • This paper summarises the recommendations of the ESUR-SPIWG for standardising the US assessment of varicoceles. This includes examination technique, image interpretation, classification, and reporting. © 2019, European Society of Radiology.