This thesis focuses on new developments (techniques, outcomes, procedures) in the field surrounding genetic counselling, in need of further research, to become part of evidence-based practice. The main aims are to examine: 1) what determines intended participation in expanded carrier screening and can this be influenced by message framing and narrative information, 2) the psychometric properties, outcomes and counselees profiles with the Dutch version of the Genetic Counselling Outcome Scale (GCOS); a potential valuable outcome measure for genetic counselling measuring empowerment, and 3) the introduction of a choice to receive predictive DNA test results by letter or face-to-face for pre-symptomatic counselees at risk of hereditary cancer compared to the traditional protocol in which counselees have to receive the results face-to-face by default.