Overview

Microsoft Advertising is building the next generation of intelligent systems that power how users discover relevant ads and how advertisers connect with customers across search, native, display, video, and emerging AI experiences. We operate at global scale, serving billions of requests.

We are seeking a Senior Applied Scientist to work across a broad portfolio of applied machine learning problems in Ads. This role spans retrieval, ranking, marketplace quality, fraud and abuse detection, content understanding, moderation, and emerging foundation-model-powered experiences. The work entails developing and applying LLMs, large retrieval models, multimodal systems, and agentic or deep-research-style workflows to high-impact advertising scenarios at scale.

This is an opportunity to work on frontier machine learning problems with direct production impact, improving relevance, quality, safety, efficiency, and advertiser outcomes at massive scale.

Responsibilities

• Design and improve large-scale learning systems for matching, relevance, prediction, classification, and decision-making in production environments.

• Partner closely with product, and platform teams to productionize models and measure impact through rigorous offline and online experimentation.

• Analyze large-scale data to identify modeling opportunities, understand failure modes, and drive continuous improvements in product quality and system performance.

Contribute to technical innovation through prototyping, experimentation, publications, patents, and strong scientific rigor.

Qualifications Required Qualifications

• Bachelor’s Degree in Computer Science, Statistics, Electrical Engineering, Computer Engineering, or related field AND 6+ years of related experience in applied science, machine learning, recommender systems, information retrieval, or related areas
  OR Master’s Degree in a related field AND 4+ years of related experience
  OR Doctorate in a related field AND 2+ years of related experience
  OR equivalent experience.

• Strong foundation in machine learning and depth in one or more relevant areas such as retrieval, ranking, recommender systems, representation learning, fraud detection, content quality, moderation

• Experience building, evaluating, and shipping machine learning models in production environments.

• Ability to design experiments, analyze results, and make data-driven decisions in complex systems.

• Strong problem-solving, communication, and cross-functional collaboration skills.

Preferred Qualifications

• Experience in Ads, search, recommendation systems, trust and safety, marketplaces, or other large-scale online platforms.

• Familiarity with large-scale distributed training, online inference systems, and latency-sensitive production services.

• Track record of technical impact through shipped systems, research publications in top tier conferences.

This position will be open for a minimum of 5 days, with applications accepted on an ongoing basis until the position is filled.

Microsoft is an equal opportunity employer. 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 with religious accommodations and/or a reasonable accommodation due to a disability during the application process, read more about requesting accommodations.