Federal Rule of Civil Procedure 26(a)(2) requires retained expert witnesses to provide an expert report which gives “a complete statement of all opinions the witness will express and the basis and reasons for them.” Fed. R. Civ. P. 26(a)(2)(B)(i). If a party fails to disclose information required under Rule 26(a)(2), “the party is not allowed to use that information or witness to supply evidence on a motion, at a hearing, or at a trial, unless the failure was substantially justified or is harmless.” Fed. R. Civ. P. 37(c)(1). As a plaintiff in the Western District of Washington recently learned, failure to adhere to Rule 26 can be fatal to a case.