Abstract Multimodal interfaces have gained considerable interest in recent years. This trend can be expected to continue as designers try to address challenges like data overload, the need for improved performance of recognition-based systems, a greater sense of immersion in virtual-reality environments, and support for time sharing and attention management in a variety of complex real-world domains. To ensure the robustness and effectiveness of multimodal interfaces, a number of design guidelines have been proposed. The present paper will review guidelines that focus on multimodal information presentation (as opposed to multimodal system input), and it will discuss important research needs in this area, including the exploration of possible uses and benefits of rarely used sensory channels (such as touch and olfaction), the consideration of crossmodal links in attention, the top–down modulation of multimodal information processing, and the need for adaptive and adaptable multimodal interfaces. Relevance to industry Multimodal interfaces will likely find their way into an increasing number of complex data-rich environments. It is critical for engineers and designers to be aware of benefits, requirements, and constraints associated with the design of multimodal displays to ensure their effectiveness and avoid pitfalls of this approach to information presentation.