Chronic wounds are a major problem in healthcare worldwide. The assessment and treatment of chronic wounds include monitoring color and size (area or volume) at regular intervals by an expert. This evaluation is often based on qualitative observation and manual measurements of the wound (using a caliper or tracing methods). Over the last two decades, several researchers have focused on developing technologies to assess the clinical improvement of chronic wounds. This article aims to provide a survey on imaging technologies applied to chronic wounds. Their accuracy, precision, reliability, ergonomics and usage are compared. In general terms, the survey aggregates the different methods into 3 groups: planimetric techniques, volumetric techniques and color classification. Finally, a discussion is provided on open topics and what progress needs to be done in this area of research. Among other key points, vision-based technologies for wound assessment should emphasize clinical validation, correlation of clinical findings with quantitative metrics and application to tele-dermatology. © 2011 ACM.