Background: Mainstreaming of germline testing demands that all healthcare professionals have good communication skills, but few have genetic testing and counselling experience. We developed and evaluated educational workshops-Talking about Risk & UncertaintieS of Testing IN Genetics (TRUSTING). Contents included: presentations and exercises, an interview with a geneticist about BRCA testing, screening and prevention implications, filmed interactions between surgeons, a genetic counsellor and geneticists with a fictitious family (proband had a BRCA2 pathogenic variant with triple-negative breast cancer, her older sister-BRCA2 heterozygous, and cousin-negative for BRCA2 variant).Methods: Twenty-one surgeons, 5 oncologists, 18 nurses and 9 genetic counsellors participated. Knowledge (18 item MCQ), communication skills (responses to 6 questions from proband and relatives) and self-confidence (discussing 9 genetic testing issues) were assessed pre- and post workshop.Results: Knowledge scores improved significantly post workshop (mean change = 7.06; 95% confidence interval (CI) 6.37-7.74; P < 0.001), as did communication (mean change = 5.38; 95% CI 4.37-6.38; P < 0.001) and self-confidence (P < 0.001).Discussion: Healthcare professionals' knowledge and self-confidence when discussing the risks and uncertainties in genetics are often poor. TRUSTING workshops significantly enhanced attendees' navigation of communication difficulties encountered and will be rolled out more widely. [ABSTRACT FROM AUTHOR]