Abstract: Provided herein are methods for generating multiplex CRISPR arrays based on annealing and ligating single-stranded DNA oligonucleotides using bridge oligonucleotides. The methods described herein include providing a first oligonucleotide comprising a CRISPR repeat sequence or a portion thereof, and a first portion of a first spacer sequence at its 3? end; providing a second oligonucleotide comprising, from 5? to 3?, a second portion of the first spacer sequence, the CRISPR repeat sequence, and a first portion of a second spacer sequence; providing a bridge oligonucleotide comprising a sequence substantially complementary to the first spacer sequence; allowing the first oligonucleotide and the second oligonucleotide to hybridize with the bridge oligonucleotide; and ligating the first and second oligonucleotide.