ESCRT-III assembles into a highly ordered filament-like hetero-oligomer. Vps20 nucleates the homo-oligomerization of Snf7 that is capped by Vps24. Vps24 recruits Vps2 and initiates Vps4-dependent ESCRT-III disassembly. ESCRT-III is required for the last steps of MVB sorting, cargo sequestration, and MVB vesicle formation.