Background. The introduction of sclerotherapy using foam sclerosants has revitalized interest in this method of treating varicose veins. Foam is made from detergent-type sclerosants already established as safe and effective in conventional liquid sclerotherapy.

Objective. European experts in foam sclerotherapy were invited to exchange their opinions and to work on consensus statements and recommendations.

Methods. A questionnaire covering different areas of foam sclerotherapy was sent to experts who have published or presented data, participated in clinical trials, or otherwise contributed to sclerotherapy with extemporary (self-made) foam. Based on the answers, several consensus statements and recommendations were approved during the consensus meeting.

Results. The use of sclerosing foam is an appropriate procedure in the treatment of varicose veins. It is a powerful tool in the hands of an expert who has sufficient experience in sclerotherapy. Sclerosing foam is more powerful than liquid. Most recommendations for conventional liquid sclerotherapy also apply to foam sclerotherapy. Some differences between these two treatments were highlighted.

Conclusion. Foam sclerotherapy is a variation of a well-established treatment that improves varicose vein management. European experts came together to harmonize their opinions about sclerosing foam. The final document reflects the experts' opinion with the aim of defining principles for a safe and effective use of sclerosing foam and for its practical application. Foam sclerotherapy allows a skilled practitioner to treat larger veins including saphenous trunks.