"[9] Yvonne's first job after gaining her degree was in the Frankford Arsenal Gauge Lab, a U.S. Army ammunition plant in Philadelphia.

[1] Clark returned to the South to get married,[7] and became the first female member of the Tennessee State University mechanical engineering department, joining the faculty in 1956.

[11][9] Clark helped to start Tennessee State's chapter of Pi Tau Sigma, a mechanical engineering society.

[13] In the summer of 1963 Clark was hired to work for NASA at the George C. Marshall Air and Space Flight Center in Huntsville, Alabama, where she investigated the cause of hot spots identified in Saturn V engines.

[14] Clark did further research that discovered methods for revitalizing and modernizing part of the inner city through the Westinghouse's Defense and Space Center in Baltimore, Maryland.

She served as the main investigator for the research project "Experimental Evaluation of the Performance of Alternative Refrigerants in Heat Pump Cycles," funded by the Department of Energy's Oak Ridge National Laboratory.

Clark was also the student division team leader for the NASA funded project at TSU called the Center for Automated Space Science.

[5] Yvonne Clark is known for her achievements as an engineer and teacher, her family attribute some of her exceptional ability to persevere through adversity or her "rhino skin" to growing up with a congenital stutter.