The first edition of Food Analysis: Theory and Practice was published in 1971 and was revised in 1978. The second edition was published in 1987, and in 1993 we found it necessary to prepare a third edition to reflect and cover the most recent advances in the field of food analysis. A complete revision of a book is an arduous and anguished task. The following are challenges that we wanted to address in this revision: to update the material without eliminating classic and time-preserved and honored methods used by the food analyst; to broaden and deepen the coverage and scope without increasing the size of the book; and to produce a textbook (for senior undergraduate and graduate students) with regard to objectives, scope, and outlay while providing a reference and resource for the worker and researcher in the field of food analysis. To meet those challenges we added much new material and took out practically the same amount of "rel­ atively outdated" material. Every chapter has been extensively updated and revised; many of the pictures in the previous editions were deleted and, whenever available and appropriate, were replaced by diagrams or flow sheets. In Part I we have expanded the seetions on sampling, preparation of sam­ pIes, reporting results, and reliability of analyses.