Senior Applied Scientist

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.