There are three major stages of the task analysis procedure contained in the handbook they are a development of preliminary performance requirements pprs b identification of subtasks c. Handbook of task analysis procedures is designed to help the reader select a specific task analysis technique for a particular situation having done this the reader can then refer to the appropriate chapter for his chosen technique this chapter provides a statement of purpose an overview and applications . Handbook of task analysis procedures praeger publishers abstract the major reason for this book is our belief that task analysis is the single most important component process in instructional systems design isd yet there is less literature available on task analysis than on any other component of isd. The handbook of task analysis for human computer interaction why do things happen when they happen trigger analysis exposes the triggers that prompt subtasks to occur in the right order at the right time and assess whether tasks are robust to interruptions delays and shared responsibility