The initial estimates made in the COCOMO II model are adjusted using a set of attributes (project cost drivers) that reflect:
1.Product characteristics such as the required system reliability and product complexity.
2.Computer characteristics such as execution time or memory constraints. These are constraints imposed on the software by the hardware platform.
3.Personnel characteristics such as programming language skills that take the experience and capabilities of the people working on the project into account.
4.Project characteristics of the software development project such as the IDE that is available and the development schedule.
The following table shows all 17 of the project cost drivers that may be taken into consideration.
| Attribute | Type | Description |
| RELY | Product | Required system reliability |
| CPLX | Product | Complexity of system modules |
| DOCU | Product | Extent of documentation required |
| DATA | Product | Size of database used |
| RUSE | Product | Required percentage of reusable components |
| TIME | Computer | Execution time constraint |
| PVOL | Computer | Volatility of development platform |
| STOR | Computer | Memory constraints |
| ACAP | Personnel | Capability of project analysts |
| PCON | Personnel | Personnel continuity |
| PCAP | Personnel | Programmer capability |
| PEXP | Personnel | Programmer experience in project domain |
| AEXP | Personnel | Analyst experience in project domain |
| LTEX | Personnel | Language and tool experience |
| TOOL | Project | Use of software tools |
| SCED | Project | Development schedule compression |
| SITE | Project | Extent of multisite working and quality of inter-site communications |