Project estimating plays a vital role in project management. Typically
completed in the initial planning stages, accurate project estimation
can be a difficult task. Organizations and project managers should use
these initial estimates to baseline the project schedule and cost, then
refine these estimates as the project develops. Accurate estimation and
refinement of the estimates leads to better and earlier decision making,
thus maximizing value. Developed within the framework of A Guide to the
Project Management Body of Knowledge (PMBOK(R) Guide) - Sixth Edition
and other PMI standards, the Practice Standard for Project Estimating -
Second Edition focuses on providing models for the project management
profession in both plan-driven and change-driven adaptive (agile) life
cycles. This practice standard describes the aspects of project
estimating that are recognized as good practice on most projects most of
the time and that are widely recognized and consistently applied. PMI
practice standards describe processes, activities, constraints, inputs,
and outputs for specific discipline subject areas and are targeted to
all practitioners within projectized organizations, not just project
managers.