After learning that mother had Native American heritage, the Department mailed notices to several tribes and the BIA. The Department discussed with the court the response to the letters, but never introduced them into evidence. The court made no order regarding ICWA compliance, though it did note that it thought the notice issues had been addressed. The appellate court reversed and remanded. The Department must file a copy of the notice sent and the return receipt as well as any subsequent correspondence. The juvenile court must receive evidence of the notice efforts and determine whether they are sufficient to comply with ICWA. The court may not consider evidence not introduced in the trial court. Here, since the Department did not introduce evidence of notice, the court did not comply with ICWA regardless of whether it made some findings of compliance.