This book uses input-output data from the World Input-Output Database to track the intermediate goods and services used in national manufacturing industries. Specifically, it examines the extent that supply chains increasingly involve imports and the extent that this trend has changed for the U.S. and other countries. The U.S. data is compared to 39 other countries between 1995 and 2009, a 15 year period. The 40 countries represented approximately 88 % of global manufacturing value added in 2009, according to United Nations data. In terms of 2009 imported supply chain value added used by a nation's manufacturing industry as a percent of all value added associated with that nation's manufacturing industry, the U.S. imported 10.8 % of its supply chain, the 3rd lowest percentage, meaning that in relation to other countries the U.S. imports a smaller proportion of its supply chain for manufacturing. Between 1995 and 2009, the percentage of imported supply chain value added increased for 32 of the 40 countries examined and for the U.S. it increased by 1.96 percentage points. The average increase for the 32 countries was 4.67 percentage points and the average change for all countries was an increase of 2.78 percentage points; thus, the U.S. percentage increase in supply chain imports is slightly below the average. China's value increased by 4.92 percentage points while Japan's value increased by 4.59 percentage points. U.S. supply chain imports peaked in 2008 at 14.2% and ranked as the 6th lowest at that time. These figures confirm that foreign suppliers have replaced some domestic suppliers in the U.S.