Process Reference Models may be developed outside of the ISO standardization providing they meet certain requirements for conformity and compliance. Process Reference Models exist or are already under development in the areas of:

• Software lifecycle processes – through ISO/IEC 12207 AMD1/2
• System lifecycle processes – through ISO/IEC 15288
• Human centered lifecycle processes - through ISO 18529
• Component-based development processes – through the OOSPICE project
• IT service management processes - through ISO/IEC 20000
• Quality management system processes - through SPICE for 9000 (S9K)
• Automotive embedded software – an initiative of The Procurement Forum and The SPICE User Group with the major European car manufacturers - through Automotive SPICE ,
• Medical device software - through the Medi SPICE initiative