You use the Monitor and Control Project Work process to keep track of a project's progress and take corrective measures when necessary. Monitoring means you compare actual and planned results, add up product defects, review progress reports, calculate performance forecasts, and assess whether implemented changes have been effective. You control activities by preparing change requests and adjusting baselines as necessary. The four stages of the Monitor and Control Project Work process are setting performance standards, observing performance, comparing actual and planned performance, and taking action to correct deviations from the plan.