Sound legal decision-making frequently requires the assistance of scientists and engineers. The survey we conducted with the cooperation of the American Academy examines the views of the legal system held by some of the nation's most distinguished scientists and engineers, what motivates them to participate or to refuse to assist in lawsuits when asked, and their assessment of their experiences when they do participate. The survey reveals that a majority of the responding scientists and engineers will agree to participate when asked, and when they turn down requests, the most common reasons are lack of time and absence of relevant expertise. Dissatisfaction with legal procedures is also a deterrent, but our respondents indicated that some procedural changes would make their participation more likely. In addition, participation appears to be associated with a greater belief in the ability of the legal system to deal well with scientific matters.