Summary Translation of the genetic code into the amino-acid sequences of proteins is essential to all life. Proteins need to be made with a certain accuracy for a cell to function properly, and an increased error rate may lead to disease. Recent results have challenged commonly held ideas on the mechanism of translation and highlighted the importance of dynamic studies, despite the fact that detailed static structures are available. Here, we will use advanced single-molecule fluorescence microscopy to study how domain rotations in a translation elongation factor contribute to enhance the fidelity of translation. Apart from offering detailed molecular insights into the essential, cellular translation process, this project also holds promise for therapeutic and biotechnological applications.