National Institute on Deafness and Other Communication Disorders (NIDCD) invites applications to support research and/or infrastructure needs leading to more accessible and affordable hearing health care (HHC). The proposed research aims should lead to the delivery of better healthcare access and outcomes and be directed to solutions that are effective, affordable and deliverable to those who need them. Outcomes and health services research are also responsive to this FOA. This FOA provides support for up to two years (R21phase) for preliminary/development studies, followed by possible transition of up to four years of expanded research and development support (R33 phase). The total project period for an application submitted in response to this FOA may not exceed five years.