Adolescence is characterized by an increase of risky behaviours. This phenomenon has a number of developmental and individual factors (among others, it depends on the need of excitement seeking and anxiety level). It is also connected to a development of future perspective and engagement in prospective activities. Anxiety level as a characteristic as well as excitement seeking remain largely stable over time, contrary to prospective activity, which can initiate and develop. Empirical evidence suggests that future orientation is related to a lower intensity of risky behaviours among adolescents. Therefore, a question was asked, whether a triggering of prospective activity can lower the tendency to risky behaviours among adolescents. In quasi-experimental study 118 participants took part. They filled in an Experience Seeking Questionnaire and Decision Preference Test before and after performing a prospective activity. Also, the State-Trait Anxiety Inventory (STAI) was used in the first part of the experiment. The results suggest that an initiation of prospective activity, formulation of personal life aims and elaboration on them, caused a decrease in the tendency for risky decisions taking, although, in accordance with the theory, it did not influence the need of excitement seeking.