requirements in part 2. One of the requirements is to use a conformant assessment method for the assessment process. The actual method is not specified in the standard although the standard places requirements on the method, method developers and assessors using the method. The standard provides general guidance to assessors and this must be supplemented by undergoing formal training and detailed guidance during initial assessments. The assessment process can be generalized as the following steps: initiate an assessment (assessment sponsor) select assessor and assessment team plan the assessment, including processes and organizational unit to be assessed (lead assessor and assessment team) pre-assessment briefing data collection data validation process rating reporting the assessment result An assessor can collect data on a process by various means, including interviews with persons performing the process, collecting documents and quality records, and collecting statistical process data. The assessor validates this data to ensure it is accurate and completely covers the assessment scope. The assessor assesses this data (using his expert judgment) against a process's base practices and the capability dimension's generic practices in the process rating step. Process rating requires some exercising of expert judgment on the part of the assessor and this is the reason that there are requirements on assessor qualifications and competency. The process rating is then presented as a preliminary finding to the sponsor (and preferably also to the persons assessed) to ensure that they agree that the assessment is accurate. In a few cases, there may be feedback requiring further assessment before a final process rating is made. Assessment model The process assessment model (PAM) is the detailed model used for an actual assessment. This is an elaboration of the process reference model (PRM) provided by the process lifecycle standards. The process assessment model (PAM) in part 5 is based on the process reference model (PRM) for software: ISO/IEC 12207. The process assessment model in part 6 is based on the process reference model for systems: ISO/IEC 15288. The standard allows other models to be used instead, if they meet ISO/IEC 15504's criteria, which include a defined community of interest and meeting the requirements for content (i.e. process purpose, process outcomes and assessment indicators). Tools used in the assessment There exist several assessment tools. The simplest comprise paper-based tools. In general, they are laid out to incorporate the assessment model indicators, including the base practice indicators and generic practice indicators.