The National Science Foundation (NSF) is offering a grant opportunity titled "WINDOWS ON THE UNIVERSE: THE ERA OF MULTI-MESSENGER ASTROPHYSICS," aimed at advancing research in multi-messenger astrophysics through the integration of observations from electromagnetic waves, high-energy particles, and gravitational waves. Proposals are sought that address coordination of observations, observations of astrophysical phenomena, or interpretation of data related to multiple messengers, with a focus on fostering collaboration and developing a skilled workforce in this emerging field. This program is significant for enhancing our understanding of the universe and is expected to award approximately 200 grants, with a submission deadline of October 15, 2024. Interested applicants can find more information and submit proposals through the NSF's grants.gov support at grantsgovsupport@nsf.gov.