Very frequently, students and clients do not do what they say they will do. Decisions and plans made in counselling sessions are often not enacted. The career development field may be better able to address the chasm between rational decisions and actual behaviour by applying the findings of behavioural economics. Behavioural economics research is revealing the predictability of irrational behaviour. Behavioural economics addresses choice, decision-making, risk and judgment, key elements of career theory and practice. Career guidance and counselling would be well served to attend to findings regarding how decisions are really made and, with some ethical caveats in mind, incorporate the management of non-rational behaviour into practice.