This book mainly introduces the research overview, results, and achievements of "The Fundamental Research for Trustworthy Software", a major research plan of NSFC. The Plan focuses on four key scientific issues: (i) measurement and modeling of software trustworthiness; (ii) construction and verification of trustworthy software; (iii) evolution and control of trustworthy software; (iv) trusted environment construction and evaluation. This book aims to establish a research framework for fundamental research on trustworthy software by focusing on the trustworthiness of embedded software and network application software, as well as the trustworthiness of software in key application fields in China. This book is intended for researchers who have been following the evolution of and trends in the trustworthy software; the book is also a valuable reference resource for practitioners and scholars at various levels and in various fields.