Principal Applied Scientist

Overview The Copilot Agents & Search Quality team develops state-of-the-art machine learning, retrieval, ranking, and generative AI technologies that power Microsoft Copilot. We solve complex real-world challenges in relevance, personalization, and information discovery at global scale, helping millions of enterprise users find the right information, at the right time, and in the right context.

We are looking for a Principal Applied Scientist with deep expertise in applied AI and a proven track record of building and shipping machine learning solutions at scale. The ideal candidate will have extensive hands-on experience developing and optimizing modern AI systems, including Small Language Models (SLMs), post-training techniques, embedding models, encoder-decoder and cross-encoder architectures, and Gradient Boosted Tree (GBT) models trained on large-scale datasets.

This is a unique opportunity to help shape the next generation of Microsoft's search and retrieval stack, driving innovations that power Copilot experiences for millions of users worldwide. You will join a fast-paced, highly collaborative environment and work closely with experts across Microsoft, including Microsoft Research, to advance the state of the art in AI-powered search, retrieval, ranking, and knowledge discovery.

Our work spans cutting-edge embedding models, cross-encoders, SLMs, deep neural networks, and classical machine learning approaches, with a strong focus on delivering measurable impact in production. Successful candidates will have a demonstrated history of leading complex technical initiatives, influencing technical strategy, and driving execution across teams while mentoring other scientists and engineers.

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 Advance the science: Design and run experiments, define and validate metrics, and develop ML pipelines and models in areas like encoder-decoder models, cross-encoder models. You will also experiment with SLMs + model distillation to bring the power of Language models optimized for focused ranking tasks within low latency constraints.

This is a strategic initiative and you are expected to drive this by working with different leaders across the org to drive clarity and alignment. You will be working with large scale data and derive insights out of it while championing Privacy and Compliance.

Drive product innovation: Partner with Engineering, PM, and Design to translate product vision and industry trends into scalable, reliable, and agile architecture. You are expected to drive long term road-maps and provide clarity and recommendations for critical investment areas for the org.

Collaborate across Microsoft: Work closely with Microsoft Research, Azure, AI platform teams, and product groups to bring cutting-edge AI into real-world applications. As a Principal Scientist you are expected to work and influence leaders in the org as well as potentially cross-org.

Champion customer impact: Engage with customers and internal teams to deeply understand pain points and drive improvements that matter. Lead and mentor: As a Principal Scientist you are expected role model deep technical expertise, generate energy towards goals, drive clarity in ambiguous situations and champion cross group/org collaboration.

You would also mentor team and scale your learnings across the broader product group. Define success: You will also help define best practices in Model evaluation and work with leaders in the org to establish and improve the process. Stay ahead: Keep up with the latest research and foster a thriving applied science culture.

Publishing is encouraged, though not required. Qualifications Required/Minimum 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. 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