The Dr. Sauer Group has been in practice for over 25 years. It was established by Dipl. Ing. Dr. Sauer, the Principal of the Group and today employs engineers and other staff at four international offices located in Salzburg, Austria (Est 1979); Washington DC, USA (Est. 1984); London, United Kingdom (Est. 1987); and New York, USA (Est. 2003).

The company's philosophy is based on the belief that motivation is derived from the individuals' success and that profession is a passion and not a burden. At the Sir Julius Wernher Memorial Lecture 'When an Invention is something new - From Practice to Theory in Tunneling 1988', Dr. Sauer expressed this with Bertrand Russell's quote: 'The secret of happiness is this: let your interests be as wide as possible, and let your reactions to the things and persons that interest you be as far as possible friendly rather than hostile'.

Upon formation, the Group provided cost effective and innovative tunneling solutions to contractors.  The benefits of such were quickly embraced by owners and today the Group is recognized as one of the leading consultants for design and construction supervision of tunnels and underground structures.

The Dr. Sauer Group has undertaken feasibility studies, conceptual design, detailed design and construction supervision, as well as expert witness and insurance risk management services for worldwide projects in a variety of environments. The experience of the Group's staff covers all aspects of tunneling engineering including, geotechnical, geological, structural design and rock support. The Group has provided consultancy and construction supervision services to a wide range of clients including owners, other consultants and contractors.

The Dr. Sauer Group's Developments include:

• The Doorframe Slab Method (DFS), a modified cut-and-cover technique which reduces the depth and disruption of open trench projects.
• The Barrel Vault Method (BVM), for shallow tunneling under buildings, or through railway embankments without disrupting surface operations.
• The Grouted Spile Anchor (GSA), for pre-stabilization of non-cohesive soil in one integrated step.
• The Drainage Rehabilitation System (DRS), which effectively controls water seepage to prevent deterioration of the underground structure, corrosion of mechanical and electrical equipment, helps to eliminate safety hazards and thus prolong structure life.
• The Waterproofing System (WS), membrane type for cut-and-cover stations, shafts, mechanized and mined tunnels and underground structures, with remedial repair system.
• The Caisson Method (CM) - patent pending, for underwater tunneling such as river crossings.

Some of the Group's Most Recent Projects that illustrate the expertise in the whole life cycle of underground structures include:

• Brunel's Thames Tunnel, London, UK - Tunnel Rehabilitation
• Red Line Subway and Seven Stars Tunnel, Israel - Conception and Feasibility Studies.
• East Side Access, MTA, New York, USA - Value Engineering.
• Beacon Hill Station, Sound Transit, Seattle, WA, USA - Detailed design and support during construction for a light rail station in soft ground.
• MBTA Russia Wharf, Boston, MA, USA - Feasibility study, detailed design and construction supervision - NATM and groundfreezing.
• MBTA Silver Line Phase III, Boston, MA, USA - Alignment study and preliminary design - Transit system including two new stations. 
• Channel Tunnel Rail Link (CTRL), Wayside Shaft, Ventilation Tunnels and Emergency Tunnels, London, UK -  Ventilation and emergency escape provision detailed design and construction supervision.
• Channel Tunnel Rail Link (CTRL), Corsica Street Shaft and Ventilation Tunnel, London, UK -  Shaft and Ventilation Tunnel detailed design and construction supervision.
• Dulles Airport Walkback Tunnel, Washington, USA - Detailed design and technical support during construction - Pedestrian tunnel.
• Santiago Metro, Chile -  Detailed design and construction supervision - Metro tunnels and stations. 
• Muni New Central Subway, San Francisco, USA - Construction method studies and preliminary design for running tunnels and stations.
• Northshore Connector, Pittsburgh, PA, USA - Detailed design for waterproofing of tunnels and stations.