SSADM (Structured Systems Analysis & Design Method)

SSADM (Structured Systems Analysis & Design Method) is a widely-used computer application development method in the UK, where its use is often specified as a requirement for government computing projects. It is increasingly being adopted by the public sector in Europe. SSADM is in the public domain, and is formally specified in British Standard BS7738.

SSADM divides an application development project into modules, stages, steps, and tasks, and provides a framework for describing projects in a fashion suited to managing the project. SSADM's objectives are to:

  • Improve project management & control
  • Make more effective use of experienced and inexperienced developmentstaff
  • Develop better quality systems
  • Make projects resilient to the loss of staff
  • Enable projects to be supported by computer-based tools such as computer-aided software engineering systems
  • Establish a framework for good communications between participants in a project

SSADM covers those aspects of the life-cycle of a system from the feasibility study stage to the production of a physical design; it is generally used in conjunction with other methods, such as PRINCE, which is concerned with the broader aspects of project management.

In detail, SSADM sets out a cascade or waterfall view of systems development, in which there are a series of steps, each of which leads to the next step. (This might be contrasted with the rapid application development - RAD - method, which pre-supposes a need to conduct steps in parallel.). SSADM's steps, or stages, are:

  • Feasibility
  • Investigation of the current environment
  • Business systems options
  • Definition of requirements
  • Technical system options
  • Logical design
  • Physical design

For each stage, SSADM sets out a series of techniques and procedures, and conventions for recording and communicating information pertaining to these - both in textual and diagramatic form. SSADM is a very comprehensive model, and a characteristic of the method is that projects may use only those elements of SSADM appropriate to the project. SSADM is supported by a number of CASE tool providers.

This was last updated in March 2008

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