Background: Challenge-based learning (CBL) is a pedagogical approach increasingly adopted in engineering education. Despite its growing practice, there is little consensus in the literature about how CBL is implemented in engineering curricula and what experiences teachers and students have in relation to it. Purpose: To address this gap, the following research questions guided the study: How is CBL currently implemented in engineering education? What difficulties and lessons learned are associated with the implementation of CBL? Methods: We systematically reviewed the empirical literature published between 2010 and 2021. Forty-eight empirical studies describing CBL implementation were analyzed using the curricular spider-web framework. Results: The review shows the variation in CBL implementation at the course and project levels. CBL courses and projects shared the use of open-ended, real-world challenges as a starting point for student learning. However, they differed in the embeddedness of a challenge in specific courses and the focus of the learning, which ranged across knowledge acquisition, knowledge application, and development of transversal skills. CBL experiences also varied in terms of challenge characteristics, such as the link with global societal challenges, stakeholders' involvement, and multidisciplinarity. Similar difficulties and lessons learned were reported by teachers and students across the different examples of CBL implementation. Conclusions: CBL as a pedagogical approach in engineering education can promote student engagement with complex societal challenges within a real-world context. However, there are limitations to the review and implications of the findings for educational research and practice.