Our Clients' Success is Our Business Dennis, Gartland & Niergarth is northern Michigan’s largest locally owned, full service public accounting firm. Founded in 1973, the firm has locations in Traverse City, MI and Petoskey, MI with experienced, professional staff dedicated to providing outstanding professional service with a personal touch to businesses and individuals throughout the region. Dennis, Gartland & Niergarth is known for its comprehensive tax, audit, technology and business consultation services, with added expertise in the agribusiness, manufacturing, professional offices, government/nonprofits and oil and gas business sectors. Our guiding principle for nearly 50 years – Our clients’ success is our business.