What is RVSM?
RVSM reduces the vertical separation of aircraft from 2,000 feet to 1,000 feet when they're flying at altitudes from FL290 (29,000 feet) to FL410 (41,000 feet).
So why is this happening? It significantly increases (in theory, it nearly doubles) the number of airplanes that can fly in a defined area of airspace. Plus, it allows pilots to pick more efficient altitudes and avoid turbulence.