If you are looking for an elegant, academic theory to suggest how contextual design might work in some controlled laboratory experiment-- this is not the book for you. This work gives step-by-step procedures on how to conduct contextual design in the real, uncontrolled world of people's lives, and how to do this work on an accelerated time schedule.
This is a clear tutorial and worthy "field manual" on contextual design, task sequence modeling, affinity diagrams, and paper prototyping for applied work in the real world.
Because it takes you through each activity step-by-step, this book does name the tools used at the time this work was crafted. Some reviewers consider that blatant advertising-- and in the case of citations for "CDTools" perhaps that's true. But in most cases it is very helpful to know that some specific products are more field-worthy than others. I strongly doubt these authors have any financial interest in boosting sales of 3M Post-It notes. (Though Amazon may profit from sales of 3M - 2051-FLT - 3M Post-it Bright Colors Memo Cube)
:-)