[영문]In 2004, we conducted a nationwide dual frame survey of landline and cell phone numbers to evaluate the feasibility of including cell phone numbers in a random digit dial telephone survey. Households with both landline and cell phones were eligible for selection in both samples. This article describes our design and data collection methods; compares the results from the two samples (with an emphasis on operational characteristics); and presents the outcomes of two experimental manipulations designed to improve the cell phone response rate