Chemotherapy-induced hair loss in cancer is usually temporary but can take a significant emotional toll on patients and lead to treatment refusal in many cases. Although hair loss is usually reversible, regrowth can take months, causing greater psychological distress. Recent years have seen the emergence of cold caps, or scalp cooling systems, designed to prevent or at least reduce chemotherapy-induced hair loss. The results to date are encouraging. We review the evidence on the effects and effectiveness of these systems, which are making their way into routine clinical practice.