Family-Owned, Colorado-Rooted Estate Planning Firm

Lewis A. Osterman

Owner and Attorney

A trusted voice among experienced Denver estate planning lawyers, Lewis works directly with individuals and multigenerational families from Highlands Ranch, Centennial, Thornton, and across the state. A University of Colorado–Boulder graduate, Lewis earned his J.D. with honors from Boston University School of Law and is an active member of WealthCounsel, a national leader in resources and support for estate planning attorneys creating high-quality, customized plans. Named a Colorado Super Lawyers Rising Star every year since joining the firm, he blends deep technical knowledge with a gift for listening—creating estate plans that fit each client’s life, assets, and values. Earlier advocacy for patients injured by unsafe medical devices showed him the high cost of courtroom battles and cemented his commitment to proactive planning. Clients appreciate his clear explanations, prompt follow-up, and genuine concern for their family’s future.

Danielle Bartell

Estate Administration Paralegal

Danielle serves as our estate administration paralegal. She joined the Osterman Law Firm with more than ten years of probate and trust administration experience. As a probate paralegal, Danielle works closely with attorneys and clients throughout every stage of the estate administration process.

Danielle received a bachelor’s degree in English Literature, graduating summa cum laude, from Colorado State University. In her free time, Danielle enjoys spending time with family and friends and working in her garden.

Amber Hups

Client Services Director

Amber serves as our Client Services Director. She helps guide clients through the estate planning process from start to finish and is dedicated to providing a seamless experience. Whether that be through helping answer questions or coordinating next steps, Amber ensures clients feel informed and supported throughout their journey with the firm.

Amber earned her Associate's Degree in Paralegal Studies in 2021. Born and raised in Colorado, she enjoys spending her free time playing Dungeons & Dragons, hosting board game nights, and relaxing with her husband, Chris, and two cats.

Olivia Coon

Administrative Assistant

Olivia serves as our Administrative Assistant. In addition to managing essential operations like scheduling, billing, and the meticulous preparation of estate plan binders, Olivia has expanded her impact by contributing to the firm’s Human Resources and Marketing initiatives.

Olivia received her Bachelor's degree in Sociology/Anthropology from Truman State University, and recently traded St. Louis, Missouri, for the Mile High City. She spends her free time crafting, reading, and hunting for the perfect latte or vintage find in Denver’s local neighborhoods.

Tanner Martin

Estate Planning Paralegal

Tanner serves as our estate planning paralegal. His primary role at Osterman Law Firm is to gather important information and prepare estate planning documents for the attorney’s review and approval prior to going out to clients. Additionally, Tanner prepares the firm’s engagement agreements and provides general legal support for our attorneys and staff.



In his free time, Tanner enjoys relaxing and spending time with his family and friends, cheering on the Kansas City Royals, and listening to the occasional podcast.

David W. Osterman

Founder (Retired)

Since founding the Osterman Law Firm in 1982, David guided Colorado families through wills, trusts, elder-law issues, and estate taxation with rigor and empathy. A Brandeis University graduate and former Law Review editor at the University of Toledo College of Law, he built the practice on meticulous work and long-standing relationships—values that continue under Lewis’s leadership. David’s dedication earned the firm an AV Preeminent® rating from Martindale-Hubbell and helped establish the WealthCounsel network of premier estate-planning attorneys. Though retired, his legacy shapes every matter we handle.