The firm was founded in 1970 by Ron Yaggy in Rochester, Minnesota, as Yaggy Associates, Inc., a civil engineering consulting firm. In late 1987, Yaggy Associates, Inc. merged with a Rochester architectural firm owned by Chris Colby. Chris joined the firm as Vice President and Director of Architecture, and the firm name was changed to Yaggy Colby Associates to reflect its new identity. 36 years later, the firm  has over 162 employees in three different states.

The Corporate office is located in Rochester, Minnesota. Regional offices are located in:

Eagan, Minnesota
Mason City, Iowa
Delafield, Wisconsin
Sparta, Wisconsin
Fort Atkinson,  Wisconsin.

Growth 1977
Land Development and Surveying services were added to the firm.
In 1977, Don Borcherding joined the firm and became Executive Vice President. A professional engineer and land surveyor, Don brought with him considerable land surveying and transportation experience.

Expansion 1979
Community Planning services were added to the firm.
Response to market needs led to the opening a new office in Mason City, Iowa in 1979. This allowed the firm to broaden our efforts in community planning and municipal engineering.

1984
Economic Development and Landscape Architecture services were added to the firm. In an effort  to meet the growing demands of the client's needs, the firm continued to expand services and  further diversify the firm by adding economic development planning and landscape architecture in 1984.

Merger 1987
Architecture
In 1987, Yaggy Associates, Inc. merged with a Rochester architectural firm owned by Chris Colby. Chris joined the firm as Vice President and Director of Architecture, and the firm name was changed to Yaggy Colby Associates to accurately reflect the new identity.

Growth 1991
Transportation Engineering services were added to the firm.
Services expanded with the growth of transportation services. The addition of Scott Samuelson, Director of Transportation in the Rochester office, led to substantial growth in transportation engineering.

Growth 1994
Geotechnical Services and Environmental Engineering services were added to the firm. Services expanded with the addition of two key professional engineers, bringing technical expertise in Geotechnical Engineering to the Rochester office and Water/Wastewater Engineering to the Mason City office.

30th Anniversary 2000
The firm celebrated its 30th Anniversary with more than 80 employees in two offices. The year also marked additional ownership and leadership transition for the firm with the retirement of Ron Yaggy. At this time the Principal ownership group was expanded to five members with the addition of Bob Ellis, Scott Samuleson, PE, and Jose Rivas, AIA.

Merger November 2000
Welch Hanson and Associates, Inc., of Delafield, Wisconsin, became a Division of Yaggy Colby Associates. With this merger the firm employed over 120 employees.

Growth August 2002
Land Management Services were added to the firm.
Services expanded with the opening of a new office in Mendota Heights, Minnesota, adding right of way and land management services.

Growth December 2004 
The firm grew with the opening of an office in Hastings, Minnesota. The additional office  provides a broadened geographical presence in the Southeast Metro and Western Wisconsin areas. With this additional office, the firm has 172 employees.

November 2006
At this time the Principal ownership group was expanded to eight members with the addition of  Terry McCarthy, Michael Court, PE, and Mark Mickelson, PE. In November 2006, the Hastings, Minnesota office consolidated with the Mendota Heights, Minnesota office to more efficiently meet the needs of the clients. The combined Mendota Heights office provided a greater range of services for new and existing clients.

December 2007- A time of transition
The end of 2007 marked ownership and leadership transition with the retirement of Don Borcherding. At this time the Principal ownership  includes: Bob Ellis - CEO, COO, Scott Samuleson - CFO, Jose Rivas,  - Secretary, Chris Colby - Principal, Terry McCarthy -  Vice President, Michael Court - Vice President and Mark Mickelson - Principal.