What is ISO/IEC TS 33061 about?  
 ISO/IEC TS 33061 defines a process assessment model for software life cycle processes, conformant with the requirements of ISO/IEC 33004, for use in performing a conformant assessment in accordance with the requirements of ISO/IEC 33002.
A process assessment model is related to one or more process reference models. The process reference model defined in ISO/IEC/IEEE 12207 is used as the basis for the process assessment model in ISO/IEC TS 33061.
A process assessment model incorporates a process measurement framework conformant with the requirements of ISO/IEC 33003 and is expressed as a process quality characteristic with a defined set of process attributes.
Who is ISO/IEC TS 33061 for? 
ISO/IEC TS 33061 on process assessment model for software life cycle processes is useful for: 
- Project managers
- Software developers
- Stakeholders
- Software testers and debuggers
 Why should you use ISO/IEC TS 33061?  
A process assessment model includes a set of assessment indicators. Process performance indicators address the process purpose and outcomes of each process in the process assessment model. Process quality indicators demonstrate the achievement of the process attributes in the process measurement framework. These indicators may also provide a reference source of practices when implementing a process improvement program.
The assessment indicators are used as a basis for collecting objective evidence to support an assessor’s judgment in assigning ratings of the performance and quality of an implemented process. The set of indicators defined in ISO/IEC TS 33061 is not intended to be an all-inclusive set and applicable in its entirety. Subsets appropriate to the context and scope of the assessment should be selected, and potentially augmented with additional indicators. A process assessment is conducted according to a documented assessment process. ISO/IEC TS 33061 provides documented assessment process that identifies the rating method to be used in rating process attributes and identifies or defines the aggregation method to be used in determining ratings.  ISO/IEC TS 33061 provides a basis for a process assessment model that is two. In one dimension, the process dimension, the processes are defined and classified into process groups together with the set of assessment indicators of process performance. In the other dimension, the quality dimension, for each process attribute in the process measurement framework a set of process quality indicators is defined for the selected process quality characteristic.
What’s changed since the last update? 
ISO/IEC TS 33061:2021 supersedes ISO/IEC 155045:2012, which is withdrawn.
ISO/IEC TS 33061:2021 cancels and replaces ISO/IEC 155045:2012, which has been technically revised. The main changes compared to ISO/IEC 155045:2012 are as follows:
- All processes and their base practices are changed to reflect the ISO/IEC/IEEE 12207 processes
- All process-related process outputs and their descriptions are revised
- This process assessment model includes a process quality attribute of process performance and can be used with other models of process quality, for instance, capability as described in ISO/IEC 33020
