Many funding agencies allow applicants to respond to referees’ comments before the applications are considered by the funding committee. It is critical to make full use of the opportunity. Referees may have considerable experience in the field of the proposed research, and it is important to consider carefully their remarks and suggestions. Chal- lenge comments that appear to be incorrect, preferably citing a reference. However, if suggestions are made that might improve the design of the study, consider carefully how the study might be modified to address the concerns, and include these in the response that will go to the funding committee. The length of the response allowed to referees' comments is usually limited, so be precise and concise.