This report completes the methodological discussion of 1997 NSAF estimation that was begun in report no. 3 in this series. Here our goal is to describe how we brought the 1997 NSAF up to census undercount-adjusted control totals. In report no. 3, a description was given of the first estimation approaches used for the 1997 survey. (Report no. 3 also explains how we brought the survey up to census-level controls.)