This study explored the use of heuristics in the design space by novice and expert engineers in the initial ideation of a design solution. Verbal protocol analyses were conducted with four engineering students and four professional engineers as they generated ideas to solve a design problem. Overall, both experts and novices used various types of heuristics. Although novices' heuristics tend to focus on improving the function of the design, experts' heuristics tend to focus on improving both function and form. The implication is that the deliberate teaching of design heuristics, along with other strategies, will help in the development of generative skills of students, stimulating more creative and innovative designs. Validated design heuristics can be integrated within engineering design content at appropriate grade levels to aid in building the repertoire of heuristics used by engineering and technology education students.