With the continuous technology advance, the feature size of nowadays integrated circuits (IC) has entered the nanometer era, which introduces many significant challenges for IC designs. This book provides an overview of these issues and further develops some potential solutions to address these important topics. The contents of this book are based upon several previous publications, which were published in top-ranked international conferences, mainly from IEEE/ACM Design Automation Conference. This book clearly describes the sources of inevitable uncertainties observed from manufactured VLSI circuits and systems, and presents substantial insights into emerging challenges for IC designs and manufacturing. Moreover, this book proposes several novel algorithms to cope with these issues, including uncertainty extraction, stochastic circuit behavior modeling and parametric yield estimation. Enriched with comprehensive illustration and extensive experiments, it is useful to IC designers and researchers who are interested with nanometer IC designs.