The global race toward practical quantum computing is accelerating, prompting an urgent effort across government and industry to prepare today’s digital infrastructure for the moment conventional encryption breaks.

Known as “Q-Day,” that theoretical milestone — when quantum computers mature to the point that they defeat current cryptographic systems — could arrive by the end of this decade, according to security experts. Based on recent White House Executive Orders to advance quantum readiness, a growing number of experts believe it could come sooner. While the exact timing is uncertain, the threat is already active. Adversaries are harvesting encrypted data today in anticipation of decrypting it once quantum capability catches up.