The purpose of this thesis is to investigate how scenarios and risks influence judgmental forecasts, forecaster’s confidence, and assessments of likelihood of occurrence. In its attempt to identify the impact of scenarios and risks as channels of forecast advice, this research reports the findings on the use of advice from six experimental groups with business practitioners as participants. Goal was to collect evidence and interpret the reasons and motivations behind judgmental forecasts from actual business life, as well as to identify the possible biases of forecasters after reviewing certain scenarios and risks. This thesis also presents analyses on the use of advice corresponding to the credibility attributes of advisors, i.e., “experienced credibility” and “presumed credibility”. Following a discussion of the results, future research directions are provided.