Principal Applied Scientist

Job Description

We are seeking a Principal Applied Scientist to lead the design, training, optimization, and deployment of large-scale AI models, including LLMs and agentic systems for advertising. This role focuses on scalable model architectures, efficient inference, and agentic capabilities that drive high-impact ad solutions. As a technical leader, you will shape strategic AI initiatives in ad retrieval, creative generation, relevance, and safety, while advancing the frontier of scalable and agent-driven AI systems. Microsoft’s mission is to empower every person and every organization on the planet to achieve more. As employees we come together with a growth mindset, innovate to empower others, and collaborate to realize our shared goals. Each day we build on our values of respect, integrity, and accountability to create a culture of inclusion where everyone can thrive at work and beyond. Responsibilities Lead the design and training of LLMs and agentic models at large scale, driving core advertising scenarios such as retrieval, generation, personalization, and safety. Innovate on model architectures, distributed training strategies, and system optimizations to ensure scalable and efficient production deployment. Develop and implement high-performance inference strategies, reducing latency and computational overhead while maintaining model quality. Partner with product and engineering leaders to integrate AI solutions seamlessly into Microsoft Ads’ global platform. Foster a culture of technical excellence, mentorship, and collaboration across teams and functions. Contribute to Microsoft’s AI research ecosystem by publishing, patenting innovations. Qualifications Required Qualifications: Bachelor's Degree in Statistics, Econometrics, Computer Science, Electrical or Computer Engineering, or related field AND 6+ years related experience (e.g., statistics, predictive analytics, research) OR Master's Degree in Statistics, Econometrics, Computer Science, Electrical or Computer Engineering, or related field AND 4+ years related experience (e.g., statistics, predictive analytics, research) OR Doctorate in Statistics, Econometrics, Computer Science, Electrical or Computer Engineering, or related field AND 3+ years related experience (e.g., statistics, predictive analytics, research) OR equivalent experience. Solid hands-on experience in designing and deploying LLMs or foundation models at large scale. Deep understanding of transformer architectures, distributed training, and model optimization for production environments. Expertise in high-performance inference techniques for latency-critical applications. Solid programming skills in Python, C++, and familiarity with PyTorch, TensorFlow, and distributed systems. Other Requirements: Ability to meet Microsoft, customer and/or government security screening requirements are required for this role. These requirements include but are not limited to the following specialized security screenings: Microsoft Cloud Background Check: This position will be required to pass the Microsoft Cloud background check upon hire/transfer and every two years thereafter. Preferred Qualifications: Experience in agentic modeling, including reinforcement learning, multi-agent systems. #MicrosoftAI Microsoft is an equal opportunity employer. Consistent with applicable law, all qualified applicants will receive consideration for employment without regard to age, ancestry, citizenship, color, family or medical care leave, gender identity or expression, genetic information, immigration status, marital status, medical condition, national origin, physical or mental disability, political affiliation, protected veteran or military status, race, ethnicity, religion, sex (including pregnancy), sexual orientation, or any other characteristic protected by applicable local laws, regulations and ordinances. If you need assistance and/or a reasonable accommodation due to a disability during the application process, read more about requesting accommodations.