The chapter provides a detailed description of W-Sec, a formal model-based countermeasures' impact assessment method. It also introduces a new formal definition of the two SysML profiles used in SysML-Sec and W-Sec, enabling (i) for the future automation of several W-Sec stages and (ii) for the definition of consistency rules ensuring the consistency of the models written in these two distinct modeling languages. In addition, the chapter evaluates W-Sec with a new industry 4.0 case-study and discusses the strengths and the current limitations of the approach in this new application field.