"Many applications stay in use for much longer than anticipated, but during the extended lifetime they will be functioning in an environment for which they have not been designed, resulting in completely new vulnerabilities and risks."

"There is a good chance that large quantum computers can be built within the next 20 years.  This would be a nightmare for IT security if there are no fully developed, implemented, and standardized post-quantum signature schemes."

Prof. Johannes Buchmann, et al, “Post-Quantum Signatures”, Oct 2004, Technische Universität Darmstadt

"The future ability of quantum computers might be a decade or two away, their future ability to break public-key cryptography has important implications for the encryption of highly sensitive information today. For these applications, we must already design new public-key cryptosystems and one-way functions that are immune to quantum cryptanalysis."

ARDA, Report of the Quantum Information Science and Technology Experts Panel, 2004