Bevacizumab (Avastin) is a humanized monoclonal antibody that inhibits the activity of vascular endothelial growth factor (VEGF), a key molecule controlling tumour blood vessel formation (angiogenesis). By inhibiting VEGF and thus tumour angiogenesis, bevacizumab inhibits tumour growth and survival. In patients with metastatic colorectal cancer (CRC), first-line use of bevacizumab in combination with fluoropyrimidine-based chemotherapy improves outcomes compared with chemotherapy alone. The side-effect profile of bevacizumab does not overlap with that of conventional chemotherapy, and it does not significantly exacerbate chemotherapy-induced adverse events. Specific side-effects of special interest for bevacizumab include hypertension, proteinuria, arterial thromboembolic events, wound-healing complications, bleeding events and gastrointestinal perforation. Oncology nurses are key to early recognition and management of side-effects, in addition to having a key role in patient education, facilitating the optimal use of bevacizumab and thus survival of patients with metastatic CRC.