NIST requests your comments on the latest revision of Special Publication 800-90A, Recommendation for Random Number Generation Using Deterministic Random Bit Generators, which is dated November 2014. This document specifies Deterministic Random Bit Generators based on approved hash functions (as specified in FIPS 180-4), HMAC (as specified in FIPS 198-1) and block ciphers (as specified in FIPS 197 for AES, and SP 800-67 for TDEA). This revision removes the previously approved Dual_EC_DRBG that was based on the use of elliptic curves and includes a number of other changes that are listed in the final appendix of the document. Both a marked-up copy and a clean copy of the document are provided for your review. Please submit comments to firstname.lastname@example.org with "SP 800-90A comments" in the subject line. Comment period closed December 31, 2014.