This report details the safety evaluations conducted for the OpenAI o1 model series, which includes the o1 and o1-mini models. The o1 models utilize large-scale reinforcement learning to enhance reasoning capabilities, particularly in the context of safety policies. The report outlines the training methodologies, including the use of diverse datasets and proprietary data partnerships, which contribute to the models' performance in complex reasoning tasks. It describes the iterative deployment process and the various safety evaluations performed, such as assessments of disallowed content, jailbreak robustness, and hallucination tendencies. The findings indicate that the o1 models have achieved significant improvements in safety metrics compared to previous models, particularly in adhering to content guidelines and resisting harmful prompts. The report emphasizes the importance of continuous refinement and the need for robust alignment methods to ensure safe deployment of advanced AI models.