Abstract Future systems will be increasingly software‐intensive, but the type of software development they will need is not well covered by current development and maturity models such as the waterfall model and Software Capability Maturity Model ® (CMM ® ). Future development of software‐intensive systems will need situation‐specific balancing of discipline and flexibility to address such issues as COTS, open source, distribution, mobility rapid change, agents, collaboration support, and simultaneous achievement of rapid development and high dependability. This article shows how the CMMI SM 's integration of modern systems engineering, software engineering, and integrated process and product development concepts provides a framework for redressing the shortfalls of the Software CMM ® , and for enabling projects and organizations to achieve the right balance of discipline and flexibility for their particular situations. But the CMMI SM has shortfalls of its own. It provides little guidance on how to define and execute specific processes for a specific project or organization. The article summarizes various process model generators for software intensive systems such as the spiral, the Rational Unified Process (RUP), MBASE, and the CeBASE Method. It concludes that the CeBASE Method best covers the full range of concerns in the CMMI SM , resolves its practice‐focus shortfalls, and covers additional best practices not in the CMMI SM , such as business case analysis, requirements prioritization, and evolution requirements. © 2002 John Wiley & Sons, Inc. Syst Eng 5: 73–88, 2002; DOI 10.1002/sys.10016