In this third edition of the now standard classroom text, Grisez and Shaw retain the best elements of the earlier versions, including their clear, straightforward presentation and use of nontechnical language. Although the basic approach, content, and organization remain substantially the same, the new edition does develop and amend some aspects of the theory. For example, the community dimension of morality is brought out more clearly and the first principle of morality is now formulated more accurately in terms of willing in line with integral human fulfillment.
Germain Grisez was a French-American philosopher and a prominent and influential Catholic moral theologian. Grisez's lengthy masterpiece is his three-volume Way of the Lord Jesus.
First of all, Grisez and Shaw don't do a great job explaining what the "new morality" is. They try to start from the basics to establish their own ethics, and that sort of works, but when they pivot to indeed staking the boundaries of their thought, the borders are still unclear. There are a number of ideas from the "new morality" that I strongly disagree with, but I wouldn't know it from reading this book; and, likewise, a number of ideas that I do agree with but am left not knowing for sure why Grisez and Shaw would argue against them.
Perhaps one of the main issues here is that the authors write about the building blocks of ethics and then transition into their own as if assuming that the building blocks obviously translate to their own ethics. But, clearly, with a diverse history in ethics, that's not the case.