EXHIBIT 99

AUTHORIZATION LETTER

April 27, 2004

Securities and Exchange Commission
450 Fifth Street, N.W.
Washington, D.C. 20549
Attn: Filing Desk

To Whom It May Concern:

By means of this letter I authorize Diane Irvine, Robert Paquin and John Geschke or any of them individually, to sign on my behalf all forms required under Section 16(a) of the Securities Exchange Act of 1934, as amended, relating to transactions involving the stock or derivative securities of Blue Nile, Inc. Any of these individuals is accordingly authorized to sign any Form 3, Form 4, Form 5 or amendment thereto which I am required to file with the same effect as if I had signed them myself.

This authorization shall remain in effect until revoked in writing by me.

Yours truly,

/s/ Joanna Strober

Joanna Strober