The NSF Directorate for the Social, Behavioral, and Economic Sciences (SBE) released last week a Dear Colleague Letter inviting members of the research community (individuals and groups) to submit by September 30th, 2,000-word-maximum white papers outlining what they think are "grand challenge" questions in the fields supported by SBE "that are both foundational and transformative". These contributions will be used to help the Directorate make plans to support research over the coming decade and beyond.