Defendant appeals her conviction for conspiracy to possess with intent to distribute methamphetamine in violation of 21 U.S.C. section 846. Defendant's contentions rest on the "buyer-seller rule," under which a conviction for conspiracy cannot be based solely on the purchase of an unlawful substance. Defendant contends that the evidence presented to the jury established only that she purchased methamphetamine from a supplier, a buyer-seller transaction, and that she was not engaged in a conspiracy with the seller in connection with subsequent distribution. She contends that the district court should have given an instruction to the jury regarding the buyer-seller rule. The judgment is affirmed, where: 1) the evidence was sufficient to support the conviction for conspiracy, given that there was an ongoing relationship of mutual trust, there was testimony that defendant was involved in the business of trafficking, there was evidence that defendant's supplier knew that defendant was engaged in redistributing the methamphetamine she was buying from him, and the supplier had an interest in fostering downstream sales; and 2) the district court did not err in refusing to instruct the jury regarding the buyer-seller rule, given that the instructions as a whole accurately informed the jury that a conspiracy could not be found based only on the sales by the supplier to defendant.