  Managing quality (such as service availability or process adherence) during
the development, operation, and maintenance of software(-intensive) systems and
services is a challenging task. Although many organizations need to define,
control, measure, and improve various quality aspects of their devel- opment
artifacts and processes, nearly no guidance is available on how to select,
adapt, define, combine, use, and evolve quality models. Catalogs of quality
models as well as selection and tailoring processes are widely missing. One
essential reason for this tremendous lack of support is that software
development is a highly context-dependent process. Therefore, quality models
always need to be adaptable to the respective project goals and contexts. A
first step towards better support for selecting and adapting quality models can
be seen in a classification of existing quality models, especially with respect
to their suitability for different purposes and contexts. Such a classification
of quality models can be applied to provide an integrated overview of the
variety of quality models. This article presents the idea of so called
comprehensive quality model landscapes (CQMLs), which provide a classification
scheme for quality models and help to get an overview of existing quality
models and their relationships. The article describes the usage goals for such
landscapes, presents a classification scheme, presents the initial concept of
such landscapes, illustrates the concept with selected examples, and sketches
open questions and future work.
