Background & aimsnWe aimed to determine if a structured workshop on fluid and electrolyte balance for junior surgical trainees led to an improvement in knowledge on the subject and to evaluate the perceived helpfulness of such a workshop.nnMethodsnSurgical trainees attended an interactive lecture-based workshop on fluid and electrolyte balance. Participants had online access to the presentation prior to the training event. They completed a multiple choice question (MCQ) test, derived from topics covered in the presentation, prior to the lecture. The MCQ test was repeated after the lecture to assess retention and application of knowledge. Participants were unaware that they would be tested and provided written feedback on their perceptions of the session.nnResultsnThirty-seven trainees from speciality training years 1 and 2 participated in the workshop. There was a significant improvement in mean test scores after the lecture when compared with pre-lecture scores (24.6/30 vs. 19.7/30, p<0.001). Trainees felt the topic and event were relevant to everyday practice (mean score 4.9/5) and that it would improve their clinical skills (4.5/5).