Adhesively bonded joints are commonly used for carbon-fibre reinforced polymer (CFRP) strengthening of concrete structures. There are a relatively large number of studies on different aspects of the CFRP-to-concrete bonded joints, however, this is not the case for bonded joints used for the strengthening of steel structures. Long-term performance and uncertainty related to environmental durability are critical barriers for the wide applications of bonded joints in structural applications. Moisture and temperature and their combined effect on both constituent material and system levels are identified as the most critical environmental factors. There is a need for studies that address short- and long-term structural behavior of the CFRP-to-steel bonded joints. This study aims to provide a review on the most recent works on the CFRP-to-steel bonded joints conducted by different active research groups in Switzerland, China, Sweden and Australia. Finally, some recommendations for future studies in this topic will be provided.