Plans

• Purpose
• Defined
  • What is a plan?
  • What is planning?
  • Levels of plan
  • The Project Plan
  • Stage Plans
  • Team Plans
  • Exception Plans
• The PRINCE2 approach
  • Philosophy
  • Prerequisites for planning -
    design the plan
  • Define and analyse the products
• Prerequisites for planning
  • Write the Project Product Description
  • Create the product breakdown structure
  • Write the Product Descriptions
  • Create the product flow diagram
• Identify activities and dependencies
  • Activities
  • Dependencies
• Prepare estimates
• Prepare the schedule
  • Overview
  • Define activity sequence
  • Assess resource availability
  • Assign resources
  • Level resource usage
  • Agree control points
  • Define milestones
  • Calculate total resource requirements and costs
• Analyse the risks
• Document the plan
• Responsibilities

Key sections

• Introduction
• Business case
• Organization
• Quality
• Plans
• Risk
• Change
• Progress
• Introduction to processes
• Starting up a projectDirecting a project
• Initiating a project
• Controlling a stage
• Managing Product Delivery
• Managing a Stage Boundary
• Closing a Project
• Tailoring PRINCE2 to the project environment
• Directing Projects with PRINCE2

The PRINCE2® approach

Prepare estimates

A decision about how much time and resource are required to carry out a piece of work to acceptable standards of performance must be made by:

• Identifying the type of resource required. Specific skills may be required depending on the type and complexity of the plan. Requirements may include non-human resources, such as equipment, travel or money
• Estimating the effort required for each activity by resource type. At this point, the estimates will be approximate and therefore provisional.

• Top-down estimating Once a good overall estimate has been arrived at for the plan (by whatever means), it can be subdivided through the levels of the product breakdown structure. By way of example, historically development may be 50% of the total and testing may be 25%. Subdivide development and testing into their components and apportion the effort accordingly
• Bottom-up estimating Each individual piece of work is estimated on its own merit. These are then summed together to find the estimated efforts for the various summary level activities and overall plan
• Top-down and bottom-up approach An overall estimate is calculated for the plan. Individual estimates are then calculated, or drawn from previous plans, to represent the relative weights of the tasks. The overall estimate is then apportioned across the various summary and detailed-level tasks using the bottom-up figures as weights
• Comparative estimating Much data exist about the effort required and the duration of particular items of work. Over time an organization may build up its own historical data regarding projects that it has undertaken (previous experience or lessons learned). Where such data exists, it may be useful to reference it for similar projects and apply that data to the estimates
• Parametric estimating Basing estimates on measured/empirical data where possible (for example, estimating models exist in the construction industry that predict materials, effort and duration based on the specification of a building)
• Single-point estimating The use of sample data to calculate a single value which is to serve as a ‘best guess’ for the duration of an activity
• Three-point estimating Ask appropriately skilled resource(s) for their best-case, most likely and worst-case estimates. The value that the Project Manager should choose is the weighted average of these three estimates
• Delphi technique This relies on obtaining group input for ideas and problem solving without requiring face-to-face participation. It uses a series of questionnaires interspersed with information summaries and feedback from preceding responses to achieve an estimate

Estimating cannot guarantee accuracy but, when applied, provides a view about the overall cost and time required to complete the plan.
Estimates will inevitably change as more is discovered about the project.

Estimates should be challenged, as the same work under the same conditions can be estimated differently by various estimators or by the same estimator at different times.

Many books and software packages include some basic rules to help ensure that an accurate and realistic estimate is produced.
Examples of such planning rules include:

• Assume that resources will only be productive for, say, 80% of their time [see 'The Complete Time Management package']
• Resources working on multiple projects take longer to complete tasks because of time lost switching between them
• People are generally optimistic and often underestimate how long tasks will take
• Make use of other people’s experiences and your own
• Ensure that the person responsible for creating the product is also responsible for creating the effort estimates
• Always build in provision for problem solving, meetings and other unexpected events
• Cost each activity rather than trying to cost the plan as a whole
• Communicate any assumptions, exclusions or constraints you have to the user(s)

PRINCE2® is a Registered Trade Mark of the Office of Government Commerce in the United Kingdom and other countries.