Project risk management is an important aspect of project management. Risk management

Risk management

Risk management is the identification, assessment, and prioritization of risks followed by coordinated and economical application of resources to minimize, monitor, and control the probability and/or impact of unfortunate events or to maximize the realization of opportunities...

 is one of the nine knowledge areas defined in PMBOK. Project risk can be defined as an unforeseen event or activity that can impact the project's progress, result or outcome in a positive or negative way. A risk can be assessed using two factors: impact

Impact

Impact may refer to:In science :* Impact , a high force or shock over a short time period* Impact crater, a meteor crater caused by an impact event* Impact event, the collision of a meteoroid, asteroid or comet with Earth...

 and probability

Probability

Probability is ordinarily used to describe an attitude of mind towards some proposition of whose truth we arenot certain. The proposition of interest is usually of the form "Will a specific event occur?" The attitude of mind is of the form "How certain are we that the event will occur?" The...

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If the probability is 1, it is an issue. This means that risk is already materialized. If the probability is zero, this means that risk will not happen and should be removed from the risk register

Risk register

A Risk Register is a Risk Management tool commonly used in Project Management and organisational risk assessments. It acts as a central repository for all risks identified by the project or organisation and, for each risk, includes information such as risk probability, impact, counter-measures,...

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