Extensions

Recent versions of CMMI from SEI indicate a "level 0", characterized as "Incomplete". Many observers leave this level out as redundant or unimportant, but Pressman and others make note of it. See page 18 of the August 2002 edition of CMMI from SEI.

Anthony Finkelstein extrapolated that negative levels are necessary to represent environments that are not only indifferent, but actively counterproductive, and this was refined by Tom Schorsch as the Capability Immaturity Model.