From the reviews:
"This book is rooted in the mathematical theory of resource constrained optimization with the goal of maximization quantitative turns ... . It attempts to broaden the portfolio discussion in two ways. First, simplified models appropriate for a new product development context are described where the lack of precise data is typical. Second, not only the annual portfolio review is discussed, but also what should be done with ideas as they emerge, and how projects should be prioritized once they are funded and ongoing." (Klaus Ehemann, Zentralblatt MATH, Vol. 1056 (7), 2005)