The first part is information coming from research studies. Such as what time of day people are happiest and what makes people happy. It goes into detail how we work to destroy our own happiness.
Part two discusses how to solve the problems outlined in the first section of the book.
Although I am not sure that I agreed with everthing Layard says. Tha book is very intresting and poses may questions about whether we have the power to change the person with have become into the person we want to be.