Introduction: The purpose of this article is to discuss whether intra-lesional alcohol injection is beneficial in the treatment of vascular malformations. Methods: A systematic review through literature search was conducted for English-language studies in PubMed. This search was conducted in April 2007 using EndNote 7.0 with keywords: 'vascular malformation*' and 'sclerotherapy'. Both retrospective and prospective studies on the efficacy of intra-lesional alcohol injection in the treatment of vascular malformations in the head and neck and/or upper extremity region published from 1997 to 2006 are included. Exclusion criteria are letters to editor, article, comment, discussion, literature research, publication review, prevalence study, animal study and lecture. Evaluation is aimed at level of clinical improvement or cure, number of injections required to achieve the desired clinical result and local or other complications. Results: Thirty publications with usable information were retrieved. In 25 publications, a total of 567 patients (mean age: 18.6 years; 43.4% male, 56.6% female) received intra-lesional absolute alcohol injection, either as an independent therapy or as an adjunctive to other treatment modalities. From 13 publications, the clinical results are as follows: excellent 74 (22.3%), good 224 (67.5%) and poor 34 (10.2%). Mean number of injections required is 2.63. Minor complications are predominantly skin damage (21.1%). Major complications are mostly tissue fibrosis (1.9%). Discussion: Intra-lesional alcohol injection as an independent treatment or in combination with other treatment modalities has good-to-excellent results. This intervention applied in fast-flow malformations is as effective as in slow-flow malformations. Preoperative and/or postoperative embolo/sclerotherapy provides substantial improvement on the overall results of the therapy. Intra-lesional alcohol injection is a relatively safe treatment modality with minor complications mostly involving the skin and some, but relatively rare, major complications. © 2010 British Association of Plastic, Reconstructive and Aesthetic Surgeons.