Quality gate

A Quality Gate is a special milestone in a software project. Quality Gates are located between those phases of a software project strongly depending on the outcomings of a previous phase. They are especially useful between those phase, where a breach in disciplines has to be overcome. A typical example for such a breach is, when embedded software must be transferred to a hardware chip. Quality Gates are not the same as milestones, because they are defined in a more general way. Consequently, Quality Gates can be used in larger set of more or less similar projects. Milestones in contrast have be defined for each project from scratch.

Each Quality Gate includes a check of the documents of the previous phase. In contrast to a software review, this check is only formal. No deep check on the contents of a documents is conducted in a Quality Gate. A Quality Gate demands a set of documents and includes special requirements on these documents. Both are held in a checklist. The check itself is done a session with decision makers and domain experts. Depending on their decision the project can be canceled, hold or proceeded normally.

Unfortunately, the term Quality Gate is not used consistently. Depending on the understanding of the term a Quality Gate can be assigned to the project management, quality management, risk management or any combination of these three management disciplines.

The term Quality Gate can be found in different software process models, e.g. in the V-Modell XT of the German federal administration. A similar concept can be found in Cooper's Stage-Gate-Model, which in contrast to the V-Modell XT is not limited to the domain of software development. Moreover, it can be used for almost all kinds of new product development. The Stage-Gate-Model also can be used to manage multiple projects, in order to extract the most promising projects and to cancel the risky projects. The goal is to concentrate resources on the more promising projects.