||The Grant Proposal Guide (GPG) provides guidance for the preparation and submission of proposals to NSF. Contact with NSF program personnel prior to proposal preparation is encouraged. Some NSF programs have program solicitations that modify the general provisions of this Guide, and, in such cases, the guidelines provided in the solicitation must be followed. (See Section C.4 below for further information on NSF program solicitations.) The Foundation considers proposals submitted by organizations on behalf of individuals or groups for support in most fields of research. Interdisciplinary proposals also are eligible for consideration.