Non-native English has become the standard language of communication in conferences with interpreting services all around the world. Previous studies have shown that interpreters consider non-native foreign-accentedness a factor that adds a layer of difficulty to their every day work. So far, most research done in the area of foreign accentedness has centred on student interpreters. This study investigates the differences between professional and trainee interpreters when presented with non-native English speech via an experimental design with a retrospective interview. The subjects are asked to shadow and interpret non-native foreign accented texts, followed by a series of comprehension questions to shed light on the strategies they used during the experiment to understand their decision processes and opinions on interpreting non-native English in general. The results show that professional interpreters’ approach and their better command at utilising different interpreting skills, allows them to have higher quality outputs and understand non-native accented speech better. On the other hand, trainee interpreters struggle with the interpreting tasks because they do not yet know how to employ the different skills effectively.