The authors present an overview of academic research on risk assessment. Consumers assess risk as though they were intuitive statisticians, combining two distinct processes to arrive at their perceptions of risk. With the bottom-up process, consumers rely on specific, individual-level risk factors. With the top-down process, consumers rely on the overall prevalence or "base rate" of a risk. Both processes may lead to over-or underestimation of actual risk, but the biases in each process stem from different sources. These sources of bias may be reduced or eliminated by implementing matching de-biasing techniques. Properly applied, de-biasing techniques may mitigate the negative consequences of over-or underestimation of risk.