The Monterey Bay Aquarium Research Institute (MBARI) is uniquely dedicated to merging science, engineering, and marine operations for the purpose of developing state-of-the-art instruments, methods, and systems for advancing scientific research in the ocean. MBARI’s Strategic Plan and Technology Roadmap set forth institutional priorities related to a series of interconnected scientific and engineering challenges that MBARI is uniquely poised to address. Applications are invited for a Principal Investigator in science or engineering to develop a research program focusing on marine microbiology, and to interact with ongoing MBARI programs that focus on the development of novel observational and analytical methods to advance our understanding of the interplay between abiotic and biotic systems in the sea. The successful candidate will be responsible for conceiving and executing original research, applying novel methods to the study of microbial processes and diversity, and for the development of technology and analytical methods in support of the objectives of the Institute. Although the position will remain open until filled, we will begin reviewing applications on March 1, 2021, and expect to begin interviewing promising candidates in April 2021.