Concern with the lack of pretesting of advance letters in demographic surveys and a desire to improve their effectiveness promoted the creation of a research agenda to research and revise the advance letter for the Survey of Income and Program Participation (SIPP). The plan to improve the SIPP Advance Letter consisted of several steps, including focus groups with field representatives, cognitive interviews with respondents, and possibly split panel testing of revised letters. This report contains the results of the first phase of this exploratory research project, which are findings from the focus groups. This report presents a description of the research methods, the research findings regarding uses of the advance letter, impediments to cooperation, and essential topics for the letter. The implications for the letter are discussed, as well as proposed letter revisions. A rough draft of the revised letter is included at the end of this report, as well as the original SIPP Advance Letter used for the focus groups.