ABOUT MERCOR Mercor's mission is to organize human intelligence to power the AI economy. We're a leading AI data company, building the layer between human expertise and frontier models. Millions of domain experts on the platform are paid over $4 million per day to train frontier AI models. Mercor's APEX benchmark family measures AI's real-world impact on professional work. Mercor Enterprise brings this same infrastructure to Fortune 500 companies: helping companies capture how their best people actually work, translating that expertise directly back into agents.   Mercor is creating a new category of work where expertise powers AI advancement. Achieving this requires an ambitious, fast-paced and deeply committed team. You’ll work alongside researchers, operators, and AI companies at the forefront of shaping the systems that are redefining society. Mercor is a profitable Series C company valued at $10 billion. We work in-person five days a week in our San Francisco, NYC, or London offices. ABOUT THE ROLE We’re looking for a Senior HR Business Partner to support Mercor’s Delivery organization. Delivery sits at the center of how Mercor turns customer demand into high-quality human data. Teams are launching and scaling accounts quickly, managing changing customer requirements, developing operators into larger roles, and making constant decisions about talent, performance and organizational structure. The HRBP supporting this organization needs to understand that environment. You will work directly with Delivery leaders and managers on the people decisions that affect whether an account and the organization perform: who we put in critical roles, how we develop strong operators, where management is breaking down, how teams should be structured, when someone needs a larger challenge, and when performance is below the bar. This is not a role for someone who wants to operate at a distance from the business. You should understand the work, the customer environment and the economics well enough to challenge leaders and make practical recommendations. Experience in the human data / AI data industry is required. You should already understand the operating model behind businesses delivering human-generated data, expert data, model evaluations, RLHF, data annotation or similar services to AI customers. WHAT YOU’LL DO - Partner directly with Delivery leadership. Advise leaders on talent, organization design, management, performance and workforce decisions as the organization scales. - Get close to the accounts. Understand the differences between teams, customers and types of work so that your people recommendations reflect the actual business rather than a generic HR model. - Raise the performance bar. Help managers distinguish exceptional performance from strong performance and performance that is below the bar. Make sure decisions are grounded in evidence and addressed quickly. - Develop strong operators. Identify high-performing SPLs, account leaders and other critical talent early. Work with leaders to create meaningful next opportunities through larger accounts, expanded scope, new problems, internal mobility or management opportunities. - Strengthen managers. Coach managers on feedback, expectations, team effectiveness, difficult conversations, performance issues and leadership behavior. Step in when a manager needs direct challenge, not simply support. - Help us retain our best people. Identify retention risk before it becomes a resignation. Understand what is driving it, including scope, compensation, manager quality, account experience, career progression and external market pull, and work with leaders on the right intervention. - Shape the organization as it changes. Partner on role clarity, organization design, succession, spans and layers, leadership changes and movement of talent between teams and accounts. - Bring a people lens to staffing and workload. Identify when persistent workload, account design, insufficient capacity or operating friction is becoming a talent problem and work with Delivery leadership to address the root cause. - Handle difficult people situations well. Support leaders through performance concerns, conduct issues, organizational changes, role changes and exits with speed, consistency and good judgment. - Run talent and performance mechanisms for Delivery. Make the company-wide approach usable in a fast-moving operating organization without turning it into unnecessary process. - See patterns before they become bigger problems. Use talent, performance, retention and employee signals to tell Delivery leadership what is changing and where intervention is needed. - Build what does not exist yet. Mercor is still early. When the business needs a new mechanism, manager tool or talent practice, you should be comfortable building the first version yourself and improving it through use. WHAT WE’RE LOOKING FOR - Human data industry experience is required. You have worked inside a company delivering human data or human expertise for AI systems, including areas such as AI training data, expert data, RLHF, model evaluation, data annotation or labeling, or closely related human data operations. You understand how these businesses actually run. - 8+ years of strong HRBP experience. You have been the primary People partner to senior leaders and can independently handle complex organizational and talent decisions. - Experience with operations or delivery organizations. You have supported teams where performance is closely tied to customers, quality, speed, capacity and execution. - High-growth startup experience. You are comfortable with rapid organizational change, incomplete systems, ambiguous ownership and a business that can look meaningfully different six months from now. - Strong business judgment. You can understand what is happening operationally, separate symptoms from root causes and make a clear recommendation. - High performance orientation. You are comfortable differentiating performance, investing disproportionately in exceptional people and addressing weak performance directly. - Excellent manager coach. You can make managers better and are comfortable challenging experienced leaders when their management approach is contributing to the problem. - Strong talent instinct. You can recognize people with unusual trajectory, understand what may cause them to leave and help create opportunities that keep them growing. - 0→1 builder. You have created useful talent, manager or organizational practices where little infrastructure existed before. - Operator mindset. You do not stop at identifying the problem or writing the recommendation. You stay close enough to the work to make sure the solution actually works. - Direct and low ego. You communicate clearly, handle disagreement well and care more about reaching the right answer than protecting your own idea. - In-person. You are able to work from our San Francisco office five days a week. WHY MERCOR This role has unusual proximity to the core business. You will work with the leaders responsible for delivering some of Mercor’s most important customer work while helping shape the talent systems behind an organization that is scaling extremely quickly. You will have the opportunity to influence how we identify and develop exceptional operators, build stronger managers, structure Delivery teams, retain critical talent and raise the performance bar across the organization. For someone who already understands the human data industry, this is an opportunity to help build the People infrastructure for one of the companies defining its next stage.