The MCA program offers an opportunity for scientists and engineers at the mid-career stage (see restrictions under Additional Eligibility Information) to substantively enhance and advance theirresearch program and career trajectory. Mid-career scientists are at a critical career transition stage where they need to advance their research programs to ensure long-term productivity and creativity but are often constrained by service, teaching, or other activities that limit the amount of time devoted to research. MCA support is expected to help lift these constraints to reduce workload inequities and enable a more diverse scientific workforce (more women, persons with disabilities, and individuals from groups that have been underrepresented) at high academic ranks. The MCA program provides protected time, resources, and the means to gain new skills through synergistic and mutually beneficial partnerships, typically at an institution other than the candidate's home institution. Partners from outside the Principal Investigator's (PI) own subdiscipline or discipline are encouraged, but not required, to enhance interdisciplinary networking and convergence across science and engineering fields. Research projects that envision new insights on existing problems or identify new problems made accessible with cutting-edge methodology or expertise from other fields are encouraged. A key component of a successful MCA will be the demonstration that the PI's currentresearchprogram could substantively benefit from the protected time, mentored partnership(s), and resources provided through this program, such thatthere is a substantial enhancement to the PI's research and career trajectory, enabling scientific and academic advancementnot likely without this support. The MCA is the only cross-directorate NSF program specifically aimed at providing protected time and resources to established scientists and engineers targeted at the mid-career stage.Participating programs in the Directorates for Biological Sciences (BIO), Geosciences (GEO), Social, Behavioral and Economic Sciences (SBE), and Education and Human Resources (EHR) will accept MCA proposals. To help identify the disciplinary program in which the MCA should be reviewed, PIs are urged to investigate the research areas supported by the different directorates and participating programs. PIs are strongly encouraged to discuss the suitability of their MCA proposal with a Program Officer from the appropriate directorate (seehttps://www.nsf.gov/bio/MCA_contacts.jsp).PIs from EPSCoR jurisdictions are especially encouraged to apply.