The history of maturity models reaches back to 1943 when Abraham Maslow defined the ‘Hierarchy of Needs’ [HOF08]. Maslow’s model makes use of most of the concepts we know from modern maturity models. He defined five levels and they all have the precondition that all goals of levels below have to be achieved in order to be able to move to upper level. Both of these concepts, levels and consecutiveness, are applied in a vast majority of maturity models nowadays. 

 

Another popular early maturity model is the Quality Management Maturity Grid (QMMG) which was developed in the 70’s [HOF08]. In contrast to Maslow’s pyramid the QMMG is a matrix but also consisting of five levels. The columns are aspect areas of quality. Within the cells, attributes act as parameter values and as often seen at modern maturity models, not fulfilled attributes provide a guideline for further improvements. 

 

Nowadays many maturity models which are dealing with various topics such as software engineering and project management exist. Many of them are focusing on process improvement in the above mentioned areas. However, maturity models focusing mostly on architecture also exist. The IT-Architecture Capability Maturity Model (ACMM) presented later in this chapter is a good example of a maturity model for Enterprise-, and IT-architectures. With the rapid emergence of Service-Oriented Architectures, SOA-Maturity Models became also popular. 

This section gives an introduction to IT-related maturity models. As all of them except the Open Group Service Integration Maturity Model are known to be based on the Capability Maturity Model Integration (CMMI), the CMMI is explained in the first place: