Numbers are the most common and complex problem trigger for interpreters. Previous research on the topic highlighted a correlation between errors and specific skill deficiencies, suggesting that this difficulty may be overcome through targeted training. However, no systematic training method has yet been developed to address this vexing problem. This article presents a constructivist, skill-based training programme designed on the basis of research findings with the aim to develop interpreting trainees’ competence in the simultaneous interpretation (SI) of numbers. The article outlines the theoretical underpinning of the training programme and its design. It then presents the results of a small-case study conducted through design-focused evaluation to explore the impact of the chosen instructional design strategies on participants’ learning process. Two groups of interpreting trainees (5 in each group) participated in the training programme and, in the end, provided the author with unstructured written feedback. The responses were analysed by qualitative thematic analysis. The analysis reveals participants’ perception of how the instructional design principles underpinning the training programme supported their learning process, leading to hypotheses for future studies on instructional design for conference interpreter training. The analysis also reports participants’ perceived training outcomes and highlights the transfer of skills and techniques to different interpreting tasks, modes and language combinations. Overall, the article aims to contribute to the field’s understanding of the difficulty in interpreting numbers and addresses the need for a pedagogical response to this challenge. It also aims to highlight the potential of instructional design research to advance the current stand of interpreting pedagogy.
