The Current Population Survey (CPS), a national survey of 60,000 households, is a major source of information about the American labor market. In January 1994, the CPS underwent a major redesign both in the wording of the questionnaire and the methodology used to collect the data. The objective of the redesign was to improve the quality and expand the quantity of available data. However, the redesign also caused changes in the measurement of many of the estimates derived from the CPS. To assess the effect of the redesign a parallel survey was conducted in two phases. During the first phase, data were collected using the revised questionnaire and collection methodology. In the second phase of the parallel survey, data were collected using the unrevised questionnaire and procedures. Using monthly data from the parallel survey and the CPS conducted during the same time period, this paper estimates adjustment factors for various aggregate measures derived from the CPS in order to permit comparisons of estimates before and after the redesign. The adjustment factors are estimated using a main effects linear model and generalized least squares. These adjustment factors indicate that the redesign had no statistically significant effect on the total unemployment rate, but it did affect statistics related to unemployment such as the reasons for unemployment, the duration of unemployment and the industry and occupation distribution of the unemployed with previous work experience. The adjustment factors also indicate that the redesign significantly increased the employment-to-population ratio and labor force participation rate for women, but significantly decreased the employment-to-population ratio for men. At the same time the redesign significantly influenced the measurement of characteristics related to employment such as the proportion of employed working part time, the proportion working part time for economic reasons, the number of individuals classified as self-employed and the industry and occupation distributions of the employed.