The paper contributes to the scholarly debate on cross-court variations in referral rates by exploring the role of the judicial hierarchy on the propensity of national judges to refer legal questions to the CJEU. The novelty of the paper lies in placing a particular emphasis on the cooperation between the first instance and appellate national courts. The questions that this paper deals with are: How do first and second instance judges perceive their role in the preliminary ruling procedure? Are there any differences between the first and second instance judges? If yes, what could explain these differences? These questions are explored from a judge-level based on the data obtained by surveying and interviewing national judges from two new EU Member States: Slovenia and Croatia.