Author Correction: Roads towards fault-tolerant universal quantum computation.

In Fig. 2b of this Review, two of the gates were inadvertently swapped. At the top right, 'Xa+c ' should have been 'Zb ', and at the bottom right 'Zb ' should have been 'Xa+c '. Fig. 2b has been corrected online. The Supplementary Information of this Author Correction contains the original, incorrect Fig. 2b, for transparency.