Using validated assessment scales for technical competence can help structure and standardize assessment and feedback for both the trainee and the supervisor and thereby avoid bias and drive learning. Correct assessment of operative skills can establish learning curves and allow adequate monitoring. However, the assessment of surgical performance is not an easy task, since it includes many proxy parameters, which are hard to measure. Although numerous technical assessment scales exist, both within laparoscopic and open surgery, the validity evidence is often sparse, and this can raise doubts about reliability and educational outcome. Furthermore, the implementation of technical assessment scales varies due to several obstacles and doubts about accurate use. In this 12-tips article, we aim to give the readers a critical and useful appraisal of some of the common questions and misunderstandings regarding the use of surgical assessment scales and provide tips to ease and overcome potential pitfalls.