Application-based market taxonomy reveals oncology supremacy, accounting for roughly four-fifths of global demand. Within this slice, therapy guidance consumes the largest budget: payers reimburse multiplexed genotyping of ctDNA to match patients to targeted agents, creating a recurring, high-margin revenue stream. Minimal residual disease monitoring, though patient-volume constrained, leverages ultra-sensitive error-corrected sequencing and carries the highest per-test price, growing >25% CAGR as adjuvant trials validate clinical utility. Early detection screens, still confined to high-risk cohorts, contribute modest sales today but scale with prospective reimbursement approvals. Beyond cancer, transplant rejection assessment—quantifying donor-derived cell-free DNA in graft recipients—generates consistent, protocol-driven testing volumes and is reimbursed by Medicare, insulating suppliers from competitive price erosion. Finally, maternal, infectious, and neurological applications remain exploratory and collectively represent <4% of 2023 revenues; their infrequency reflects limited clinical-evidence thresholds and fragmented regulatory pathways.