The use of consultant interpreters is recommended. Being qualified conference interpreters themselves they are in close touch with the needs of conference delegates and clients all the time (which is what generally distinguishes them from commercial translation companies or other language service providers that only act as agents). With expertise acquired over the years at many different events and gatherings, they are a great resource for clients when it comes to providing high-quality interpreting services for a specific event - because no event is ever like any other.
Consulting a professional conference interpreter in good time can help you save money and improve communication at your event.