d Abstract] Mikhail Alekhnovich ∗ Subhash A. Khot † Guy Kindler ‡ Nisheeth K. Vishnoi § We show that, unless NP⊆DTIME(2poly log(n) ), the closest vector problem with pre-processing, for ℓp norm for any p ≥ 1, is hard to approximate within a factor of (log n)1/p−ǫ for any ǫ > 0. This improves the previous best factor of 31/p − ǫ due to Regev [19]. Our results also imply that under the same complexity assumption, the nearest codeword problem with pre-processing is hard to approximate within a factor of (log n)1−ǫ for any ǫ > 0.