probability and impacts to be used when assessing and prioritizing individual project risks. Definitions of risk probability and impacts. Definitions of risk probability and impact levels are specific to the project context and reflect the risk appetite and thresholds of the organization and key stakeholders. The project may generate specific definitions of probability and impact levels or it may start with general definitions provided by the organization. The number of levels reflects the degree of detail required for the Project Risk Management process, with more levels used for a more detailed risk approach (typically five levels), and fewer for a simple process (usually three). Table 11-1 provides an example of definitions of probability and impacts against three project objectives. These scales can be used to evaluate both threats and opportunities by interpreting the impact definitions as negative for threats (delay, additional cost, and performance shortfall) and positive for opportunities (reduced time or cost, and performance enhancement). Table 11-1. Example of Definitions for Probability and Impacts +/- IMPACT ON PROJECT OBJECTIVES SCALE PROBABILITY TIME COST QUALITY Very High >70% >6 months >$5M Very significant impact on overall functionality High 51-70% 3-6 months $1M-$5M Significant impact on overall functionality Medium 31-50% 1-3 months $501K-$1M Some impact in key functional areas Low 11-30% 1-4 weeks $100K-$500K Minor impact on overall functionality Very Low 1-10% 1 week