Oscar Lilienthal
Development Manager
- 15+ years delivering projects across healthcare, education, workplace, life sciences, commercial office, and luxury residential sectors
- Construction and project management leader specializing in cost estimating, budgeting, preconstruction, and financial management
- Known for developing accurate budgets, managing project financials, and maintaining cost certainty throughout design and construction
About
Oscar is a seasoned construction project manager specializing in cost planning, financial oversight, and delivering complex projects across diverse sectors. He joined Seneca Group in 2025, where he supports West Coast corporate clients with a focus on executing high-impact construction projects. Based in Seattle, he brings over 15 years of experience in project management across multiple construction firms, with strong expertise in regional market dynamics.
His portfolio includes commercial, healthcare, education, life sciences, and high-end residential projects, equipping him to manage a wide range of project types and stakeholder needs. Oscar is particularly skilled in developing project budgets from Conceptual Design through Construction Documents, ensuring financial clarity from early planning through execution.
He has extensive experience in estimating, managing, and overseeing project financials, consistently delivering accurate cost projections and maintaining budget alignment. His analytical approach and attention to detail enable clients to make informed decisions and achieve successful project outcomes.
Oscar holds a Bachelor of Science in Construction Management from the University of Washington.
RECOGNITIONS & ACCOMPLISHMENTS
- 2017 peer-nominated employee of the quarter award
- 2020 peer-nominated "people award"
- American Alpine Club Member
- Washington Trails Association Volunteer
Features
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