This paper presents an evaluation of Trauma-Informed (TI) training for police officers in the West Midlands Police from November 2022 to February 2023. The West Midlands Violence Reduction Partnership has commissioned and delivered bespoke TI training since 2020, which aimed to deepen the understanding of adverse childhood experiences (ACEs) and trauma within the Police and, in turn, to create meaningful changes in everyday policing practice. Pre- and post-training surveys were conducted with 230 frontline officers and new recruits, as well as semi-structured interviews with 14 police officers and sergeants. Statistically significant improvements were found across all seven factors measured by the Trauma Aware Policing Attitudinal Survey (TAPAS). These findings indicate the efficacy of the training in improving police officers’ knowledge, responses, behaviours, self-efficacy, reactions to work, and personal and system-wide support for trauma-informed care. The qualitative results indicate a positive influence of the TI training on police practice overall. However, the quantitative data have limitations in drawing conclusions regarding long-term knowledge retention and the integration of trauma-informed practices, as well as the lack of robustness of the TAPAS tool. This highlights the necessity for further efforts to assess TI attitudes and providing TI training to police officers and senior management, promoting ongoing professional development and the wider implementation of trauma-informed approaches.