For nearly a half century, Eisenhour was a pioneer and leader in the modern era of highway construction. After working as an engineer with the Michigan Department of State highways starting in the mid 1930's, he formed his own company in 1947 and its eventual success made "Eisenhour" a well-known name in the road-building industry. Specializing in concrete paving, Eisenhour's major contributions were developing the mixing of concrete in a central location and perfecting the slipform paving process, now standards in the industry. With the increased productivity from these innovations, the company set national paving records while constructing thousands of miles of highway and dozens of airport improvement projects. His national reputation and pre-eminence as a concrete paving contractor brought him considerable recognition and honors, including president of the Michigan Road Builders Association and life director of the Associated General Contractors of America.